Second Language Acquisition (SLA) is a critical issue to both teachers and learners of a second language equally. Thus, teaching and learning a second language has always been of a highly important issue for linguistics who always seek language learning solutions to facilitate instructors job and answer educational enquires .Fillmore and Snow, 2002 and Hamayan, 1990 stated that teachers can play a positive role in improving second language acquisition if they understood how to improve the learners ability of majority. This paper will be devoted to Stephen Krashen's second language learning acquisition theory. It will go through the stages of the theory and some applicable strategies for L2 teachers and learns.
Key words: second language acquisition, learning, L2, theory
Linguist Stephen Krashen (1981,1982) , University of Southern California, USA has developed the most famous second language acquisition theory (SLA) which is also known as the Krashen's Monitor Model. This adult second language acquisition theory is mainly developed for second language learners (L2) who are hypothesized to have two different independent systems for developing their ability in second languages acquisition and conscious language learning. So these systems are interconnected in an explicit way where subconscious acquisition appears to be far more important as it takes place naturally. The theory rotates around hypotheses that young learners subconsciously pick up the target language similarly to acquiring their mother tongue in informal situations. In fact, this is totally different from formal learning where it is thought to be dominated by error correction and the presentation of explicit rules (Krashen and Seliger,1975). In this paper, I will shade light on SLA theory, it's components and how important for the L2 teachers to be familiarizes with it.
Acquisition and learning
Both the mother tongue and the second language acquisition share different aspects. They both require a meaningful interaction, authentic communication in which speakers are paying the most attention for conveying and understand the message rather than the form of their utterances. Error correction is tend to be less important and explicit teaching of grammar is not relevant to language acquisition, teaching should give acquisition an adequate chance to flourish and make the second language learner gains a self confidence so later on he will realize his mistakes and overcome them as this technique will help the acquiring process. (Brown and Hanlon, 1970; Brown, Cazden, and Bellugi, 1973).
Whereas, formal language learning is thought to be overwhelmed by a great deal of error correction and the existence of explicit grammatical rules (Krashen and Seliger, 1975). Although error correction is maintained, helps the learner come to the correct mental representation of the linguistic generalization it is said that it hinders the language development and makes the learner always tense governed by error phobia . Whether such feedback has this effect to a significant degree remains an open question (Fanselow, 1977; Long, 1977).
2. The natural order hypothesis
This hypothesis in second language acquisition assumes that mastering second language grammatical rules occurred in a predictable order. Regardless of the mother tongue of the learners, acquiring the target language rules varies in terms of their sequential so some rules are acquired earlier than others. Yet, second language grammar should not be taught as it is supposed to be acquired in this natural order.
3. The monitor hypothesis
This hypothesis states that acquiring an L2 will be developed automatically allowing the acquirer to monitor his new language grammatical rules and edit the mistakes unconsciously at some stage, which we will see later, which is called the Monitor.
These monitor uses vary from a learner to another, with different degree of accomplishment. Stephen Krashen (1981) classify the monitors into two types, Over-users who always try to use their Monitor, and end up "so concerned with correctness that they cannot speak with any real fluency." Monitor Under-users either have not consciously learned or choose to not use their conscious knowledge of the language. Although error correction by others has little influence on them, they can often correct themselves based on a "feel" for correctness.
Teachers should facilitate presenting the best possible monitor users as to promote communication and avoid hindering acquisition with grammatical rules domination.
4. The input hypothesis
As it is mentioned earlier, the Krashen's theory of SLA is also called the input hypothesis, which answers the question of how a target language acquirer develops competency over time. It states that a language learner who is at "i level" must receive sufficient and logical input that is at his level "i" and a new "+1".The new "+1" varies from a learner to a another where "x" can pick something different form "z " depending on his background, interest, priority, attention and the way it is presented.
Teachers should focus on varies methods of teaching, a sufficient input and encouraging fluency rather than accuracy.
5. The affective filter hypothesis
Filtering the learner's input varies from a stage to another, so a learner of a second language might not need to filter every single input at the early stage. The role of filtering the new input increases as the learner have sufficient comprehensive input. At later stage when the second language learner masters a lot of L2 rules and have reached the advanced language proficiency, filtering becomes subconscious process. This process will shape the new language and internalize its rules forming a native like competency.
The above five hypotheses of L2 acquisition can be summarized as follow:
1. Acquisition is more important than learning. 2. For acquiring a new language, two conditions are essential. The first is logical input containing i+1, formed a bit above the learner's current level, and second, a low affective filter to allow the input takes place.
Development of second language acquisition
Stephen Krashen's concept of second language acquisition "intake' means presenting a language context a "little beyond" the learner's current competence in the L2 ( Krashen, 1981,p.103). He sometimes refers to it as i+1, meaning that the learning situations should challenge the L2 acquirer by presenting a new input and above the learner's level so that he will acquire something new and construct on what he already has . The concept of the continuum of learning, is said to be a shared phenomenon by most current language theorists, where predictable and sequential stages of second language development occurs. A child can acquire a second language using almost the same techniques he applies in acquiring his mother tongue. In fact, it requires authentic situational interaction in the second language and meaningful communication in which the two parties are concerned not with the form of their words but with the message they are conveying and comprehending. Error correction and explicit teaching of rules are not relevant to language acquisition (Brown and Hanlon, 1970; Brown, Cazden, and Bellugi, 1973). The second language learner progresses from no knowledge of the new L2 to a level of competency closely like a native speaker. These theories however, have identified different stages for the development of second language acquisition where they are identified in five phases:
Stage 1, the receptive or preproduction stage
This stage is also called the silent stage where the learners develop survival vocabulary, following different teaching and learning situations including playing, miming, simple games and listening to stories. This phase could last from hours to six months. As the learner feels comfortable, he/she starts understanding and interacting with the teacher, his classmates and the surrounding environment using a variety of techniques like pointing to surrounding things, standing up, closing the door, nodding or might responding using simple words like "yes" or "no". Teachers are recommended not to force learners to speak at this stage.
Stage 2,the early production stage
After acquiring about 5000 words in the first stage, the learner adds 1000 active words, in another six months, enabling his/ her to speak one or two words phrase, and demonstrates understanding by responding to yes/no, some WH questions or either or. New vocabularies are required to be presented side by side with revising the old ones. Mistakes are to be tolerated in speaking provided the message is understandable.
Stage 3, the speech emerging stage
The most prominent phenomenal of this stage is the production of L2 phrases and simple sentences. During the second year, the learners will start interacting using the second language in reading and writing for operational purposes. The surrounding should play a positive role in encouraging the L2 learner and ignoring mistakes as long as the message is understandable and clear.
Stage 4,the intermediate fluency
At this stage the L2 learner is more aware of the usages of academic words in different situations comprehending about 6000 active words. He/she can interacts outside the teaching and learning contexts without using L1 for interpretation thus, he still makes errors in complex grammar and the usages of new vocabulary. The learner can interacts in academic presentations using visual and hands-on science activities, solve math problems, making models, maps, participate in academic discussion, make brief oral presentations and answer higher level questions. easier. situations
Stage 5, the advanced language proficiency speakers
This level can be mastered after from five to seven years. The learner can comprehended academic presentations without using visual illustrations, he can uses higher reading comprehension skill, writing comprehension, reports and research papers. The learner can use L2 using grammar and vocabulary comparable to his age native learners.
Understanding the learner's stage helps the instructor to tailor the material accordingly and build on the existing strengths and remedial the weaknesses.
The Role of the First Language in Second Language Acquisition
Mother tongue interference has been of a high priority in the history of second language acquisition researches and practices. For a long time , it had been reputed that the main source of syntactic errors in adult L2 performance was the performer's mother tongue (Lado, 1957), in addition to a great deal of materials preparation was done with this assumption in mind (Banathy, Trager, and Waddle, 1966). Consequently, experimental studies of errors made by second language learners guided to the discovery, however, that many errors are not definite to the structure of the first language, but are common to second language users of different linguistic backgrounds (e.g. Richards, 1971; Buteau, 1970). These findings have led several researchers to examine the value of contrastive analysis and to argue instead for error analysis. As clearly stated earlier, the mother tongue is one of a number of causes of error but other factors need to be measured.
A research conducted by Selinker, Swain, and Dumas, 1975; Plann and Ramirez, 1976 found that , first language influence appears to be strongest in complex word order and in word for- word translations of phrases. First language influence is weaker in bound morphology. First language influence seems to be strongest in "acquisition poor" environments. And finally first-language-influenced errors here are also in the domain of word order.