The Implications of Child Language Acquisition for English Oral Instruction

: This article endeavors to clarify the five principal hypotheses posited by Krashen, delving into the intricacies of child language acquisition's characteristics and patterns. Through this exploration, the intention is to provide valuable insights that can inform and enhance oral instruction in the domain of English language teaching. Krashen's hypotheses, encompassing the Input Hypothesis, Affective Filter Hypothesis, Monitor Hypothesis, Natural Order Hypothesis, and the Input Hypothesis, serve as a foundational framework for understanding the dynamics of language acquisition. By scrutinizing these hypotheses, this study seeks to unravel the nuanced interplay between language input, affective factors, conscious monitoring, the inherent order of acquiring linguistic elements, and the role of comprehension in the language learning process. In parallel, an examination of child language acquisition becomes pivotal, considering the unique characteristics and patterns exhibited during this developmental phase. Insights into the natural, instinctive processes through which children acquire language can offer valuable pedagogical implications. Understanding how children intuitively grasp language nuances, build their linguistic competence, and navigate the intricate path of acquiring a second language can significantly inform instructional strategies aimed at fostering effective oral communication skills in English language learners. In essence, this article aspires to bridge theoretical constructs with practical applications, providing a comprehensive understanding of Krashen's hypotheses and their implications for optimizing oral instruction in the context of English language teaching.


Introduction
In recent years, English language teaching has placed increasing emphasis on the cultivation of students' comprehensive English language proficiency, which includes both language fundamentals and communicative abilities.Among these abilities, "listening and speaking" play a crucial role.However, the focus on exams and scores in English education in our country has led to a "mute English" teaching approach, where students lack confidence and freedom to express themselves in English.Consequently, it has become an urgent issue to address how to encourage students to speak English boldly and freely in current teaching practices.
Stephen D. Krashen, an American linguist and educator, proposed that "any scientific theory is composed of a series of hypotheses."Krashen's second language acquisition theory consists of five hypotheses: the acquisition-learning hypothesis, the natural order hypothesis, the monitor hypothesis, the input hypothesis, and the affective filter hypothesis.By studying these five hypotheses, we can identify the characteristics and patterns of efficient language acquisition in children.

Krashen's Second Language Acquisition Theory
Among the numerous theories of second language acquisition, Krashen's five hypotheses are regarded as the most comprehensive and influential.This theory primarily explores the strategies and practical applications of his proposed second language acquisition theory in second language teaching, further summarizing and refining the relevant theories and strategies in second or foreign language learning research in recent decades.Krashen's second language acquisition theory consists of five hypotheses: the acquisition-learning hypothesis, the natural order hypothesis, the monitor hypothesis, the input hypothesis, and the affective filter hypothesis.Based on the study of these five hypotheses, one can derive the characteristics and patterns of efficient language acquisition in children, and provide some suggestions for English speaking teaching.

Acquisition-learning Hypothesis
According to Krashen's Acquisition-learning hypothesis, he states, "There are two independent processes involved in developing second language proficiency: 'acquisition,' which is a subconscious process and shares fundamental similarities with the way children acquire their first language, and 'learning,' which is a conscious process through which language can be 'known.'"Based on this hypothesis, children acquire their first language through an unconscious process of forming language cognition through guessing.This process of language mastery in children can be referred to as "natural acquisition."Children naturally and effortlessly engage with language, acquiring language proficiency through continuous language usage, leading to their remarkable linguistic abilities.
Building upon this hypothesis, G. Dehaene-Lambertz and E.S. Spelke conducted relevant research on human cognitive development, and their findings suggest that even in infancy, human cognitive abilities undergo significant enhancement over time and environmental changes.This early cognitive capacity reflects the superiority of infants in language acquisition compared to other animals.Additionally, the hypothesis of "neural commitment to the native language" proposed by American scholar Kuhl suggests that the specialization of the human brain's regions is not yet complete during early infancy.The "non-specialized" development of the infant brain enables their auditory and articulatory systems to be more sensitive and rapid than those of adults, making it easier for them to perceive and distinguish different languages.Consequently, children can acquire a second language naturally and effortlessly, similar to acquiring their first language.In contrast, as adults undergo brain maturation, the specialization of brain regions and the formation of pronunciation and auditory organs gradually occur, leading to the completion of "neural commitment to the native language."Adults experience a decreased ability to discriminate and master different phonetic, lexical, and grammatical features of languages, along with a reduced sensitivity to languages other than their native tongue.At this stage, their path to developing proficiency in a foreign language relies primarily on conscious efforts to learn language rules and accumulate knowledge, a process known as "language learning."Krashen's acquisition-learning hypothesis posits that, in terms of second language acquisition outcomes, acquisition is more effective than learning in enhancing language proficiency for learners.

Natural Order Hypothesis
Krashen asserts that regardless of learners' age composition, native language differences, or disparities in learning conditions and environments, language acquisition follows a natural sequence and pattern.The natural order hypothesis was initially proposed by Corder S.P., an expert in applied linguistics from the United Kingdom.Corder argued that certain rules are acquired earlier in the language acquisition process, while others are acquired later, indicating the predictability of the order in which second language learners acquire language rules.However, the difficulty level of language rules does not significantly influence the formation of the natural order, nor does the sequencing of rule instruction by teachers in the classroom have a substantial impact.In 1973, Brown et al., through long-term observational studies of three children, discovered that these children followed a specific sequence in their English language acquisition process, with different morphemes being acquired at different times.Krashen synthesized and analyzed the content and findings of these studies and further conducted a series of experimental research.He concluded that regardless of learners' age, native language, or cultural background, they universally adhere to a fixed natural acquisition order in second language acquisition.For example, the present progressive tense is the easiest and earliest acquired morpheme, while possessive forms are typically acquired at a later stage.
This natural sequence of language acquisition can provide insights to educators.If language learning aims to develop language competence and language usage, both teachers and students can deviate from a fixed language sequence in the teaching process.Instead, they should flexibly engage in language acquisition based on their own characteristics and regularities while adhering to the natural order of acquisition.By doing so, they avoid being constrained by rigid and uniform standards.However, Krashen also suggests that when learners are in natural communicative and instructional environments, they acquire language according to the natural order.However, when learners' psychological mechanisms and dynamics change (such as when evaluating and monitoring the process and outcomes of second language acquisition), this natural order of acquisition may undergo alterations.
As learners, children adhere to certain sequences or patterns in language acquisition.Children learn their native language to fulfill their needs, and therefore, they place more emphasis on oral expression.To express every aspect accurately through language, children imitate phonetics and intonation, repeat language multiple times, and attempt to present their thoughts or needs in different ways for comprehensive expression.

Monitor Hypothesis
This hypothesis is closely related to the acquisitionlearning hypothesis.The unconscious and natural nature of language acquisition enables students to effortlessly acquire fluent oral communication skills, while the conscious and rule-based nature of language learning involves monitoring or editing language usage using correct rules.The core of the Language Acquisition Device (LAD) theory proposed by American linguist Chomsky is the innate language acquisition ability in children.Chomsky argues that humans possess a genetically determined language acquisition device within their cognitive structure, facilitated by existing knowledge and genetic mechanisms.This device is present in all typically developing children and enables them to effortlessly acquire language without explicit instruction.By inputting basic language materials, children can transform the received information through the language acquisition device into internalized grammar and produce output accordingly.
Building upon this research, Krashen's monitor hypothesis elucidates the relationship between unconscious acquisition and conscious learning in the language acquisition process.Learners, after grasping the structural framework and language rules, employ monitoring to check and correct their language usage.However, in the process of language use, excessive focus on rule application can lead to a psychological phenomenon known as "the affective filter," where learners become overly self-conscious about using correct language structures and rules.This excessive selfconsciousness can create purposeful anxiety, causing abnormal psychological changes, hesitation, slowed speech, and even an inability to speak.Within the monitor hypothesis, Krashen categorizes monitor users into three types: overusers, under-users, and optimal users.According to this classification, children are considered under-users of the monitor (uninhibited speech), while college students often fall into the category of over-users (reluctant to speak).

Input Hypothesis
Krashen introduced two additional hypotheses, the "input hypothesis" and the "affective filter hypothesis," in his work "Principles and Practice in Second Language Acquisition."He considers the input hypothesis to be a central component of second language acquisition theory as it addresses the fundamental question in language teaching: how to acquire a language, particularly a foreign language.According to Krashen, sufficient comprehensible input is a necessary condition for second language acquisition.Learners, when exposed to target language materials through listening or reading in a natural language environment, activate their innate language acquisition mechanisms when the difficulty of these materials slightly exceeds their current language proficiency.This natural language acquisition process is what Krashen refers to as "optimal input," expressed by the "i+1" formula, where "i" represents the learner's current language level and "+1" represents material slightly above the learner's current level.By ensuring an adequate amount of comprehensible input, learners' language proficiency can progress from level "i" to level "i+1." During the process of language acquisition, children have the opportunity to access sufficient "comprehensible input" and ensure "optimal input quantity" when the necessary conditions are met.This pattern aligns precisely with the four characteristics of Krashen's input hypothesis.
1. Comprehensibility: Parents engage in conversations with children using vocabulary and language structures that are slower in pace, simpler, and easy to comprehend.This is crucial for ensuring children's language acquisition.If the difficulty level of language input surpasses the child's comprehension abilities, they will struggle to understand the meaning, rendering communication meaningless.
2. Interesting and Relevant: In the process of learning English, children are often exposed to practical communicative teaching materials such as pictures, nursery rhymes, stories, and short plays.Simple and interesting teaching materials and methods allow children to experience the joy of learning language.Therefore, the more engaging and relevant the language input is, the more naturally children will acquire the language without even realizing it.
3.Not Grammatically Sequenced: Children can acquire correct language expressions through comprehension and imitation.This language proficiency is not developed through deliberate instruction but rather naturally over time, as a result of receiving a sufficient amount of appropriate language input.4. Sufficient i+1 Input: Placing children in suitable language environments and providing them with ample and meaningful language input activates their "language acquisition device" in their brains.For example, in bilingual or multilingual educational settings, children not only avoid language confusion but also promote brain development and enhance cognitive abilities.

Affective Filter Hypothesis
Krashen argues that although sufficient comprehensible input is a necessary condition for second language acquisition, even in such an environment, it does not necessarily guarantee effective language learning.The learning outcomes of learners during the input process are influenced by emotional factors, which act as filters on language input.If learners have clear learning goals, adapt well to the learning environment, and can relax and accept language learning, the "affective filter" is weak.Conversely, if these conditions are not met, the affective filter is strong.Language input must pass through the affective filter to be transformed into "language acquisition," and the amount of language absorption depends on the learner's receptiveness.
Based on this hypothesis, children, due to their immaturity in age, psychology, and cognitive development, exhibit high plasticity and receptiveness in the process of language acquisition.Firstly, children have clear and simple learning purposes and motivations, which allows for greater flexibility in their learning attitudes, providing them with relatively stable psychological qualities during the acquisition process.Moreover, children acquire language unconsciously and without awareness, making the entire process relaxed and enjoyable.As a result, children have a weaker affective filter.In comparison, adults have already developed and completed their first language acquisition, with mature physiological and psychological indicators.Their language acquisition plasticity is reduced, resulting in diminished learning abilities.Specific manifestations include lack of motivation, fear of making mistakes, decreased confidence, and emotional anxiety.Therefore, adults have a stronger affective filter.

Implications for English Oral Instruction
In summary, the analysis of children's language acquisition characteristics and patterns using Krashen's five hypotheses provides several insights for English oral instruction.These insights can be summarized as follows:

English Oral Proficiency Development
In the context of English oral proficiency development, teachers should strive to employ an immersive teaching approach in the classroom.They should create contextualized and authentic language environments that resemble the natural language contexts of native speakers.Students should engage in dialogues, communication, and problem-solving activities within realistic or simulated situations, either individually or in collaborative teams.This allows students to learn language rules, develop language intuition, and refine their language skills through repeated practice.
Outside the classroom, teachers should encourage students to explore authentic English resources such as songs, movies, and TV shows.By immersing themselves deeply and repeatedly in these resources, students can strive to achieve authentic pronunciation, intonation, and oral expression.Additionally, students should actively participate in group activities that involve English communication, such as English corners, speeches, debates, etc.Through practical interaction and continuous experimentation, students can apply language skills, accumulate knowledge, enhance their oral proficiency, and eventually develop their own expressive style.

Follow the Order and Patterns of Oral Proficiency Acquisition
Regardless of the learners' stage, they follow certain sequences or patterns in language acquisition.The sequence and patterns of acquisition vary among individuals due to learner differences.To explore the suitable sequences and patterns for learners, it is essential to understand their learning purposes throughout the acquisition process.For example, children learn their native language to meet their needs, so they focus more on oral expression.To accurately express everything in language, children imitate phonetics and intonation, repeat language multiple times, and try different ways to present their ideas or needs.On the other hand, students learning a second language aim to complete assignments and exams, and they concentrate on answering questions, emphasizing written expression.In order to acquire accurate language, students prioritize language instruction, follow language rules, and continuously correct and adjust their language usage.
The process of oral proficiency development is purposeful, rule-based, and systematic.Considering the different learning purposes, stages, and characteristics of students, the cultivation of English language skills should have different emphases.The process of language learning progresses from input (listening, reading) to memory storage and then to output (speaking, writing).Adequate input is necessary to build up memory storage, which enables accurate and fluent output when needed.Looking at English education in China from primary school to university, each educational stage has its own focus.For example, in primary school, English education emphasizes learning through interest, allowing children to engage with English in a relaxed and natural environment.In middle school, grammar rules are emphasized, and students familiarize themselves with grammar through extensive exercises.In university, English education emphasizes vocabulary accumulation and practical language activities.It is evident that there is a lack of continuity and coherence between different stages of education.For instance, there is a significant decrease in the input of language usage skills between primary and middle school.In university, students still need to spend a considerable amount of time on repetitive input of language basics, while the cultivation of output skills is neglected.This is why many university students diligently study grammar, do exercises, and pursue certificates but still struggle to communicate smoothly in English.Therefore, it is crucial to prioritize the development of students' listening and speaking abilities while purposefully increasing the input of cultural knowledge and relevant humanities and social sciences.This not only appropriately distributes the input volume of foreign language learning but also enhances students' output skills.

Effectively Employing the "Monitoring" Mechanism
Under the monitoring hypothesis, the foreign language learning environment can be divided into two types: natural communication environment and classroom learning environment.Based on different learning environments, learning approaches can also be categorized as subconscious acquisition and conscious learning.Unlike the subconscious acquisition that occurs in natural communication environments for children, learners in school settings predominantly engage in conscious learning.The entire learning process involves students incorporating the guidance provided by teachers with their own cognition to form a personal language knowledge system, which is subsequently employed for communicative output.During the communication process, learners activate the "monitoring" mechanism based on their language system to verify and correct language production (writing and speaking).For English major students, who acquire language knowledge through conscious learning, effectively utilizing the "monitoring" mechanism becomes particularly crucial.Firstly, it is essential to employ "monitoring" in different stages of the learning process: during the preparation phase, activate prelearning "monitoring" to establish study plans; during the implementation phase, employ the "monitoring" mechanism to explore suitable learning methods; during the feedback phase, utilize "monitoring" for continuous error correction.Secondly, learners should learn to use monitoring appropriately: excessive monitoring can constrain expression due to excessive adherence to rules, while insufficient monitoring hinders the ability to evaluate language output accuracy against language rules.Adequate monitoring helps learners express themselves fully while facilitating timely error correction, ultimately achieving the desired learning objectives.Within a monitoring framework, learning allows students to transform the knowledge taught in classrooms into their own knowledge construction, transitioning from conscious learning stages to subconscious acquisition stages, thus effectively enhancing language skills and enabling students to attain accurate and fluent oral communication abilities.For teachers, it is crucial to understand that student errors are inevitable as students apply language in practice, influenced by the natural order of acquisition and activating the monitoring mechanism for self-correction.Therefore, when teachers notice student errors during oral classroom instruction, they should refrain from immediately interrupting and correcting them.Such interruptions shift students' attention from conveying information to monitoring language, thereby transforming subconscious learning into conscious learning and diminishing the effectiveness of student oral output.Teachers should create language-rich environments for students while guiding them to leverage their language aptitude based on individual differences, fostering students' ability to regulate monitoring-using it sparingly or not at all-to efficiently utilize language and express ideas naturally and fluently.

Ensuring Input Quantity and Quality
Ensuring both the quantity and quality of language input are crucial factors for successful language acquisition.In oral teaching, teachers should not only rely on textbooks but also create an environment that provides learners with a continuous supply of comprehensible language materials.Taking the "Speech and Eloquence" course as an example, teachers should not only impart theoretical knowledge on speech skills and eloquence but also encourage students to practice extensively through visual, auditory, and oral exercises.Visual input involves watching original English speeches to stimulate interest in public speaking.Auditory input entails listening to a large volume of authentic pronunciation to enhance language learning efficiency.Speaking input builds upon the foundational visual and auditory inputs, allowing students to effectively transform what they have learned into spoken output, thereby achieving effective oral language acquisition.The quality of language input is another critical factor influencing the success of students' oral language acquisition.High-quality language input should possess three characteristics.First, the input language should be comprehensible.Teachers should use clear and understandable language during oral instruction to ensure efficient absorption of language information and knowledge by students.Additionally, teachers should select language materials of varying levels based on students' individual differences to ensure correct comprehension.Second, the input language should be interesting and relevant.The more interesting and relevant the language materials are, the higher the success rate of natural language acquisition for learners.For example, in "Business English Negotiations" teaching, when introducing negotiations between Chinese and American companies regarding pricing for a product, teachers should compare relevant Chinese and American cultures.This enables students to understand cultural differences and apply cross-cultural communication thinking in negotiations, ultimately achieving effective communication.The input of relevant background knowledge not only helps students gain a more comprehensive and in-depth understanding of the learning content but also stimulates their interest in communication.It allows them to apply the learned background knowledge to language contexts, thereby enhancing their overall language proficiency and core personal qualities.Third, non-grammatical programming should be employed.Efficient language learning is based on respecting the principles of language acquisition.Disregarding these principles leads to passive learning and no significant gains.Therefore, teachers should not be restricted to a fixed and unchanging sequence during the teaching process.They should adjust their teaching methods and concepts, transitioning from being mere instructors to collaborators.The content and sequence of instruction should be tailored to students' proficiency levels and actual needs.Students, too, should shift from being mere recipients to active participants, using classroom knowledge as a basis and their own language systems as the core.They should exercise their subjective agency, actively engage in oral practice, and gradually enhance their oral expression abilities.

Reducing Affective Filters
According to cognitive psychology, the decisive factor in language learning is not the methods and tools used but rather the learner's internal psychological development and cognitive abilities.Students may experience symptoms such as increased heart rate, sweaty palms, stiff facial expressions, and trembling voices when speaking English in the classroom.Psychologically, they may feel anxious, tense, self-doubting, or other negative emotions.Excessive anxiety can also lead to difficulties concentrating and a blank mind, which are symptoms of foreign language anxiety.The higher the level of foreign language anxiety, the more evident the obstacles to oral language input and the poorer the learning outcomes.To help students reduce the negative impact of anxiety, teachers should understand the causes of anxiety and how to create an environment that lowers affective filters.The causes of foreign language anxiety include motivation, confidence, and anxiety levels.The teaching atmosphere directly affects the factors that contribute to anxiety.In teacher-centered classrooms where teachers act as judges and students are evaluated, especially in the presence of negative feedback, students may feel pressure and lack confidence in front of their peers, leading to increased anxiety.Therefore, in oral teaching, cooperative learning methods should be employed more often to create an open and relaxed environment for language practice, allowing students to engage in lively conversations with peers of similar proficiency levels in a collaborative and stress-free atmosphere.The evaluation of tasks can also evolve from solely teacher feedback to group or intergroup feedback.Feedback from familiar peers is more easily accepted and adopted by students, thereby alleviating the anxiety associated with oral practice.For example, during professional English oral practice in the classroom, each group can form a company based on their interests, and members can choose roles related to their preferred professions for role-playing.In subsequent case-based activities, students take on different responsibilities and tasks based on their chosen professions.After completing the tasks, each group's achievements are presented to all members.Regardless of success or failure, the results are obtained through the collective efforts of all members, allowing each individual to experience a sense of accomplishment and pride.
Such cooperative learning methods create an immersive environment for students, enabling them to experience the use of language to solve problems firsthand.It provides them with opportunities for mutual assistance and learning, ultimately reducing the affective filters of learners and improving their oral expression abilities.

Conclusion
By applying Krashen's "five hypotheses" theory, this study investigates the characteristics and patterns of children's language acquisition.Based on this, suggestions are proposed for modern English oral instruction, aiming to enhance students' overall language proficiency.