The Value of SLA Main Theories on Foreign Language Learning and Teaching in Vocational Colleges

Along with the development of linguistic science, the second language acquisition (SLA) has become an independent subject. Its theory is widely accepted and applied to the foreign language-teaching field. The mark theory, the mother tongue transfer theory, language input theory, cultural introject theory and so on have important enlightenment and the value to the foreign language teaching and the study in vocational colleges and can promote the solution of the present problems.


Introduction
Before 1920's, basically, the SLA theory serves the foreign language teaching.From 1980's,with the consummation of it, it is developed into an independent discipline.How the foreign language teacher guides the student to learn the foreign language in particular as their foreign language base is comparatively low?Teachers pay more attention to such kind of questions.This article starts from the explanation of the native language and the second language, makes the brief elaboration to the theory and attempts to elaborate its value to the foreign language learning and teaching in vocational colleges.

The Native Language and the Second Language
The first language refers to the mother tongue, namely, native language, but it is not always like this, an American born in China, his mother tongue is English, but the first language is a Chinese.The second language is the other language, which is different from the mother tongue.It is usually acquired in the corresponding language surroundings.The mother tongue, the first language, the second language usually are obtained in the certain language environment, therefore, we call it "acquisition" .The foreign language study as it is not in the corresponding language environment, we call it "the foreign language study".There isn't the linguistic environment, there isn't real acquisition.The theory is suitable to the foreign language teaching in some degrees.

Mark Theory
Frubetzhoy in Prague School first proposed it in 1930's.Latter, it is applied by Jacobson, the representative of this school, to the phonemics study.Jacobson used it in the glossary study and indicated "the unmarked word easier exquisite than the marked word.Similarly, as in the language acquisition" Chomsky has developed the mark theory, and utilized it in the transformational grammar.Simultaneously, he has pointed out that the core grammar is unmarked, but the peripheral grammar is marked.Namely, the mark theory divides the language features into two kinds: The unmarked and the marked.In the process of foreign language learning, the language learner keeps the basic cognition rule---from easy to difficult.
The author held that unmarked language phenomenon is relatively easy; it is also relatively easy to obtain in the language learning process.For instance, the past form and past participle of the regular verbs are much easier to remember than those of the irregular verbs.According to the mark theory, we may determine the foreign language learning order, the arrangement of the textbook content and the content order for what the teacher taught.In the process of foreign language learning and teaching, we should enlarge the stimulating of the marked language phenomenon, namely enlarges the input of the marked language material module.At the same time, we also borrows the word" mark" to make the special "mark" for the marked content in ours thought and in our memory.We should carry on special mark in our actual training and note taking.

Mother Tongue Transfer Theory
Lado (1957) believed that, the mother tongue transfer is that the language learner unconsciously utilizes the mother tongue (knowledge) in the second language learning process.Selinker (1983) defined the Positive transfer and the Negative transfer: If two language structures are similar, then the mother tongue transfer will be the Positive transfer; Otherwise, the Negative transfer.Ellis also pointed out it is much more obvious in the early period of the second language acquisition for the mother tongue.If you can not understand the background of foreign language culture, Possibly the negative transfer for the native tongue will be made to cause the failure of communication..If you said to a foreigner "Did you have your lunch?"He possibly thought you must ask him to have lunch..Moreover, the Chinese likes modest.But it is not such for English and American.If our modest migrates to study English, it maybe makes awkward situations.Otherwise, if this kind modest migrates to study Japanese, it is useful.
The author believed, in the process to the second language learning, it is more similar to the native language, much easier to study.For instance, the direct translation from Chinese into English I study English.At the same time, the simple sentence is easy to learn, the compound sentence includes the multiple clauses, especially in professional foreign language, is much more difficult to grasp.Moreover, in the process to the foreign language teaching and learning, we must grasp the similarities between the mother tongue and the foreign language, use the positive transfer functions to make the learner to learn the foreign language quickly and correctly.Simultaneously we must highlight the differences and the contrasts of the two languages, reduce the negative transfer of the mother tongue, understand the difference in the contrast, grasp the characteristics of the foreign language at various levels from the differences.For example, when we study the English passive voice, we must emphasize the English passive structure "subject -predicate -object" has the approximate corresponding relation with Chinese structure " object -predicate-subject".But in the process of Japanese study, we must emphasize Japanese sentence structure "subject -object -predicate" has some relation with Chinese order "subject -predicate-object".It also need point out the non-language factors have the language consciousness, the thinking mode, the age, the mother tongue level, the environment and so on, so we must raise learners' language consciousness, the foreign language thought, improve the level of mother tongue, create the good language learning environment.When we are teaching foreign language, our explanation should be with the multimedia live video, the establishment linguistic environmental simulation or real-background translation to increase the positive transfer and reduce the negative transfer, make the student think in foreign language, make good use of the simulation and real place surroundings.

Language Input Theory
Krashen, Long, and Chomsky etc. once have made some elaboration about the theory.American linguist Stephen D. Krashen proposed the monitoring theory, which is "the most comprehensive, most accepted theory."(Rod Ellis, 1986).Started from 1975, he has made thoroughly carefully research to the second language acquisition, formed the input theory with the foundation of the five suppositions, namely, The Acquisition-Learning Distinction Hypothesis; The Natural Order Hypothesis; The Monitor Hypothesis; The Input Hypothesis; The Affective Filter Hypothesis.

The Acquisition-Learning Distinction Hypothesis
This is the starting point of Krashen's theory; it is the most basic hypothesis.Krashen explains the concept of " study" as" acquisition " and "1earning ". "Acquisition " is the language learning process with "subconscious, unofficial, natural, and even appropriate to gleaning styles ". "Learning " refers to" learning the language rule consciously officially, explicitly ".Before Krashen, people generally thought only the child has the natural absorption language ability, after " critical period ", people can only depend upon on initiative study, to grasp the second language.But Krashen's theory actually proposed that, adults depend upon two ways for the developing competence in a second language: First, likes the child learning mother tongue, the acquisition with subconscious, natural, unconscious absorption of the language and the language rule similarly obtained unconsciously to shape "language feeling", we call it "Language acquisition/natural learning".Second, learning the language regular process consciously, we call it " Language learning ", the adult still has the competence of natural absorption language.Krashen holds people who want to grasp the second language mainly depend on the acquisition.
But the author believes that the adult who grasps the second language must use the two ways to develop it simultaneously, pay attention to the " Language learning ", as well as exert the function of " Language acquisition "to promote language communicative abilities.To the vocational foreign language teaching, first, is to learn the language knowledge consciously; second, is to acquire the language communicative competence unconsciously.The classroom instruction mainly manifests for learning the language rule and form consciously, but learning the language rule is extremely limited to the development of the language communicative competence, its main function is only in monitoring and the revising the language.The fluent expression of the language learner primarily lies in the language grasped unconsciously in the natural scene.Therefore, the classroom foreign language teaching should stress the language rule study, as well as carry on the communicative activities mutually to let the language learner accept the input unconsciously, and gradually get the language system in brain, achieve the goal of grasping the language skillfully.
The teacher may use the real scene or the real social language simulation scene in the foreign language teaching classroom in the vocational foreign language teaching to make the abstract language concrete and visualized.To explain, practice foreign language in the concrete scene can promote the studying, understanding, the memory and the utilization ability of foreign language.Moreover, the establishment "the social foreign language corner" ---this language scene can also increase practice opportunity of the foreign language and the help foreign language learner gradually establishes the direct relation for the foreign language and the objective social language scene, bring them up to think with the foreign language to achieve the goal to utilize the language in the real communicative situations.

The Natural Order Hypothesis
When Krashen summarizes the American second language teaching experience, he discovered that, No matter what the first language (mother tongue) is, no matter what difference of their cultural context is, the general order of which they grasp foreign language grammar as the second language is approximately same, that is to say, some grammar structures acquire comparatively early, some grammar structure acquire later.Krashen obtains this kind of natural order when he analyzes the experimental acquisition of the second language.Krashen also believes that, the mother tongue is not the interference of all at the second language acquisition.
At the author's point of view, that, our foreign language study and the teaching must be acted in an orderly way, must be according to the certain objective order and rule, so suitably utilizes Chinese can accelerate the foreign language acquisition.Nearly all of our foreign language learning is acquired inclines environment, if we regard Chinese as the barrier for learning foreign language, and not allow the teacher to use Chinese in their teaching activity, It will inevitably affect the foreign language the study.Especially to the teaching of vocational college, as the student's foreign language level is relative low, so reasonably, suitably utilizes Chinese can help the student to be better, quickly understand the foreign language, and accelerate the acquisition of the foreign language.

The Monitor Hypothesis
It is believed that as Krashen proposed, the human's cerebrum has two independent languages systems ---conscious monitoring system and subconscious system.In the process of language study, once the monitoring system has affected its function, it will have the edition and control function to make the language user to pay attention to the use of the language form but not the language content expression.The author assure that, in the process of foreign language study and teaching, it is not suitable to be anxiously or excessively to corrects the students' wrongdoings, but should start its language monitoring system, to make use of the function of the two kind of monitoring systems, and emphasized the student "subconscious monitoring", lets the student pay attention to concentrate on the actual activity in the classroom and naturally practice self-error correction.

The Input Hypothesis
According to Krashen's input hypothesis, the language acquisition is made through receiving massive understandable information; teacher's main energy should put in providing the best language input for the students to accelerate the language acquisition.Krashen has enumerated the four essential conditions of the best language input: (1) understandable; (2) interesting, close correlative; (3) not to use the grammar as the outline;(4) massive.Regarding the Comprehensible Input, Krashen thought it should be included: The overall language difficulty should not surpass the learners' learning capability (to be able to understand by the learner), but contains slightly higher language structure than that of the learners' existing language ability." Its pattern is "i+1", "i" stands for the learners' existing level, +1stands for the new language ingredient and the language form which the language information contains."Long also believes that, no matter is the mother tongue or the foreign language learning, the successful learners always obtains the understandable language input.Mr. HuZhuanglin believed as well, the learners' contacted language level should maintain the certain disparity with the existing level of the learners'.----The majority of contents may be understood, but still some have challenge to them (Hu Zhuanglin: P291).Chomsky emphasizes this essential factor of "the rich environmental stimulation "is "the rich language input" in the foreign language teaching practice.
The author believed that, in the process of foreign language study, "the rich moderate language input which may be understandable" is extremely important.It is because only the language inputs turns into the language absorption, the language learner can really grasp the foreign language.Therefore we should enlarge the input amount and the difficulty appropriately on the base of the language learner's existing foreign language proficiency to achieved ideal condition of " understandable language input", but we must pay attention to the language input way should be changeable.As above mentioned, this is also in the language teaching and in the study process, we must use many kinds of input patterns to make the language input as the language absorption to enhance teaching and the learning effect.In the process of foreign language teaching practice in the vocational college, we must pay more attention to the quality and quantity of language input for classroom teaching and learning.The classroom teaching and learning quality and quantity directly relate to the efficiency of the vocational college foreign language teaching and learning.The student's learning capability is also under the constant training, their self-study ability also need strengthen constantly.This requests the teacher to make full use of the classroom, the teaching place, under the guidance and the help of teacher's to enhance student's foreign language ability continually.Moreover, the student's foreign language foundation is generally lower, and requests the teacher to be able to grasp the quality and quantity of the classroom language input well.In the classroom teaching and learning, the teacher should pay attention to the clear pronunciation, language input speed and use more common words or less uncommon words; much standard language, less slang; more simple sentence, less the complex sentence, provide the moderate reading material for the students.Maintain "i+l" level is the ideal input level.

The Affective Filter Hypothesis
It is Dulay and Burt who propose the theory in1977 in relation to the supposition of the different emotion with the non-mother tongue acquisition, and it aims to explain the emotion factor influences foreign language study.They define it as "one kind of intrinsic processing system, it prevents language learner's the language absorption through the emotion factor subconsciously ".Krashen has developed this theory, and thought it as " one kind of psychological barrier which prevents language learner to completely digest the comprehensive input obtained in the language learning ".It believed that, the existing massive suitable inputs environment is certainly not to be equal to that the student can learn the target language well, the second language acquisition is also influenced by the emotion factor.The language input must be filtered through the emotion filter, and then it has the possibility to turn the language" absorption" (in-take).Krashen divides the emotion factor into three kinds: (1) motivity: The students with big motivity acquire much more; (2) self-confidence: The strong self-confidences person acquire s many; (3) anxious degree: The low anxious degree is advantageous to the second language acquisition.Because the ability of the adult emotion filters is stronger than that of the child, therefore the input effect is lower than the child.American psychologist Rogers thought that, "The successful teaching relies on the kind of sincere understanding and the trust relations between teachers and students, relies on the kind of harmonious security classroom atmosphere." The author suggested that, the foreign language study and the teaching must pour into the power to enhance the self-confidence, create a kind of low degree emotion filter environment to remove the psychological barrier, reduces the emotion filter degree, as the input premise and the input effect guarantee.Therefore, we should make the correct use of the classroom appraisal terminology and manifest the thought delaminating teaching, attach importance to the students' emotion factors, reduces the emotion filter degrees.The emotion filter is an important factor, which affects the foreign language study.The low emotion filter foreign language learner can study well, while the high emotion filter learners study is not very well.To improve student's classroom participation enthusiasm, to lower reduces the students' emotion filter of foreign language learning, the teachers' classroom appraise terminology are the most important.Teachers should inspire the students much more, help them to establish self-confidence.It is also important to guide the student to maintain the learning interest, create ease, friendly and comfortable learning environment for the student, to guarantee lower emotion filters in the study.Besides much more uses of the commendation classroom appraisal terminology for the students, as the vocational college students' English proficiency differences are bigger, the classroom appraisal terminology also manifest the lamination teaching thought.Regarding the students with learning difficulties, teachers should not criticize at will in the classroom, but give them much more affirmation, much more encouragement appraisal, even if they make a bit progress, teachers should promptly praise them, encourage them to strengthen their learning confidence.

Cultural Introject Theory
Schumann (1978) was the earliest person who proposed the theory.He pointed out; the language learner 's extent of target language culture introject determines the language acquisition degree.Brown (1980) defines it as "the language learner's adaptation to new culture process".They believed that, the social distance among the language learner's native language and the target language and the psychological distance determine the culture introject level, thus determine the language acquisition.The social distance includes: Target language speaker with the second languages acquisition person, whether they treat each other equally, whether they hope the second languages acquisition person to be assimilated, whether they hoped to share society facilities, the second languages acquisition community's size as well as attaching strength size, whether the culture is in consistent with the target language culture, whether they hold the affirmation manner to each other, the time of the second languages acquisition person hope to study in target language region factors.The mental distance includes the factors such as language shock, cultural shock, motive, and self-awareness.Schumann also believed that, social distance factor's function is much bigger.The aim to study language lies in the use of language, the use of language cannot part from the linguistic environment (including locutionary context and situation and cultural context), but the culture also is an important constituent of linguistic environment, therefore the culture has similarly the vital significance to the language study.For example, to the beginner, we must give them to input the language with common style, along with the improving of language learning level, the language style input should be diversified to train the learner's language consciousness, to make them use the corresponding language style in different situations to obtain the language appropriateness (for details see Xu Haiming 1998).For instance, the Chinese studies English, as a result of Chinese culture influence, when we are greeting somebody, we commonly use salutation sentences as "Have you had your meal?", "where are you going?" etc., but the English native speaker usually says with not actual content greetings, like "Good morning", "It is a nice day" and so on.Therefore, if you want to grasp their language, you must first understand their culture.Certainly, the learner's attitude, the first language role, the age, the emotion individual difference and so on are also important factors, which affect the language learning.
The author believed that, the target language culture amalgamation would greatly promote the language acquisition person's study; it is an extremely important link to train the language learners "language consciousness".Therefore, adding corresponding foreign literacy class or the cross cultural communication class is of great help to the foreign language study, simultaneously in the foreign language teaching practice, it is also necessary to interlude culture input and it is also essential to the foreign language to grasp the foreign language thinking mode.

Conclusion
We made plain explanation on the main theories of SLA and proposed the value to the vocational college foreign language teaching and learning.It is necessary to point out that each kind of theory and its value is certainly not isolated, some are mutually affect and supplement each other.We must use these theories dialectically.The relative theories of SLA provide us ponder and research direction to enhance the teaching efficiency for the vocational college foreign language teachers, especially to improve the quality and quantity of the classroom teaching and learning.The above theories also broke through the classroom instruction category and promoted the socialization for language teaching and learning.The current vocational college foreign language teaching idea and the educational model also wait for the further discussion and the research.