Second language acquisition
Second language acquisition or second language learning is the process by which people learn
a second language in addition to their native language(s). "Second language acquisition" refers to what the learner does; it does not refer to what the teacher does (see "language education" for work on language teaching). "Second language acquisition research" studies the psychology and sociology of the learning process. Sometimes the terms "acquisition" and "learning" are not treated as synonyms and are instead used to refer to the subconscious and conscious aspects of this process respectively (see second language learning). "Second language" or "target language" or "L2" are used to refer to any language learned after the native language, which is also called "mother tongue", "first language", "L1", or "source language". Second language acquisition also includes third language acquisition/multilingualism and heritage language acquisition. Second language acquisition may be abbreviated as "SLA", or "L2A", for "L2 acquisition". Second Language Acquisition and its premises
Second language acquisition encompasses the acquisition of any language after the acquisition of the first language by a learner. Therefore, it incorporates learning the third or fourth languages which is closely related to bilingualism and multilingualism, and heritage language learning. Cenoz and Genesee (1998)terms multilingual acquisition and multilingualism as complex phenomena and add that they implicate all the factors and processes associated with second language acquisition and bilingualism as well as unique and potentially more complex factors and effects associated with the interactions that are possible among the multiple languages being learned and the processes of learning them. Valdés (2000) defines heritage language as the language someone learns at home as a child which is a minority language in society, but because of growing up in a dominant language, the speaker seems to be more competent in the latter and feels more comfortable to communicate in that language. However, since heritage speakers are commonly alienated from their heritage language for a long time, and get limited or no exposure to that language, they seem to be in a state of language acquisition that is greatly different from monolinguals or second language speakers of that language
Developmental patterns；Ellis (1994) distinguished between "order" to refer to the pattern in which different language features are acquired and "sequence" to denote the pattern by which a specific language feature is acquired.
1;Order of acquisition Researchers have found a very consistent order in the acquisition of first language structures by children, and this has drawn a great deal of interest from SLA scholars. Considerable effort has been devoted to testing the "identity hypothesis", which asserts that
first-language and second-language acquisition conform to the same patterns. This has not been confirmed, perhaps because second-language learners' cognitive and affective states are so much more advanced, and perhaps because it is not true. Orders of acquisition in SLA often resemble those found in first language acquisition, and may have common neurological causes, but there is no convincing evidence for this. It is not safe to say that the order of L1 acquisition has any easy implications for SLA.
Some research suggests that most learners begin their acquisition process with a "silent period", in which they speak very little if at all. It is said that for some, this is a period of language shock, in which the learner actively rejects the incomprehensible input of the new language. However,
research has shown that many "silent" learners are engaging in private speech (sometimes called "self-talk"). While appearing silent, they are rehearsing important survival phrases and lexical chunks. These memorized phrases are then employed in the subsequent period of formulaic speech. Whether by choice or compulsion, other learners have no silent period and pass directly to formulaic speech. This speech, in which a handful of routines is used to accomplish basic purposes, often shows few departures from L2 morphosyntax. It eventually gives way to a more experimental phase of acquisition, in which the semantics and grammar of the target language are simplified and the learners begin to construct a true interlanguage (Seidner, (1982), pp. 9-10). The nature of the transition between formulaic and simplified speech is disputed. Some, including Krashen, have argued that there is no cognitive relationship between the two, and that the transition is abrupt. Thinkers influenced by recent theories of the lexicon have preferred to view even native speaker speech as heavily formulaic, and interpret the transition as a process of gradually developing a broader repertoire of chunks and a deeper understanding of the rules which govern them. Some studies have supported both views, and it is likely that the relationship depends in great part on the learning styles of individual learners.
A flurry of studies took place in the 1970s, examining whether a consistent order of morpheme acquisition could be shown. Most of these studies did show fairly consistent orders of acquisition for selected morphemes. For example, among learners of English the cluster of features including the suffix "-ing", the plural, and the copula were found to consistently precede others such as the article, auxiliary, and third person singular. However, these studies were widely criticized as not paying sufficient attention to overuse of the features (idiosyncratic uses outside what are obligatory contexts in the L2), and sporadic but inconsistent use of the features. More recent scholarship prefers to view the acquisition of each linguistic feature as a gradual and complex process. For that reason most scholarship since the 1980s has focused on the sequence, rather than the order, of feature acquisition.
2; Sequence of acquisition
A number of studies have looked into the sequence of acquisition of pronouns by learners of various Indo-European languages. These are reviewed by Ellis (1994), pp. 96–99. They show that
learners begin by omitting pronouns or using them indiscriminately: for example, using "I" to refer to all agents. Learners then acquire a single pronoun feature, often person, followed by number and eventually by gender. Little evidence of interference from the learner's first language has been found; it appears that learners use pronouns based entirely on their inferences about target language structure.
Studies on the acquisition of word order in German have shown that most learners begin with a word order based on their native language. This indicates that certain aspects of interlanguage syntax are influenced by the learners' first language, although others are not.
Research on the sequence of acquisition of words is exhaustively reviewed by Nation (2001). Kasper and Rose (2002) have thoroughly researched the sequence of acquisition of pragmatic
features. In both fields, consistent patterns have emerged and have been the object of considerable theorizing.
Another line of theory and research uses cognitive science to seek to understand how second language (L2) learners internally process language information. In doing so, formal understandings have been challenged, as these cognitive approaches have offered alternative conceptions of SLA processes. Below, I give an overview of the major products of cognitive speculation and research. Specifically, I describe cognitive-related concepts and evidence related to how individuals (1) structure L2 knowledge, (2) use those structures to comprehend and produce in second languages, and (3) restructure language knowledge as their L2 proficiencies increase.
Structuring Second Language Knowledge Some of the major cognitive theories of how learners
organize language knowledge are based on analyses of how speakers of various languages analyze sentences for meaning. MacWhinney, Bates, and Kliegl (1984) found that speakers of English, German, and Italian showed varying patterns in identifying the subjects of transitive sentences containing more than one noun. English speakers relied heavily on word order; German speakers used morphological agreement, the animacy status of noun referents, and stress; and speakers of Italian relied on agreement and stress. MacWhinney et al. interpreted these results as supporting the Competition Model, which states that individuals use linguistic cues to get meaning from language, rather than relying on linguistic universals. According to this theory, when acquiring an L2, learners sometimes receive competing cues and must decide which cue(s) is most relevant for determining meaning.
These findings also relate to Connectionism. Connectionism attempts to model the cognitive language processing of the human brain, using computer architectures that make associations between elements of language, based on frequency of co-occurrence in the language input (Christiansen & Chater, 2001). Frequency has been found to be a factor in various linguistic domains of language learning (Ellis, 2002). Connectionism posits that learners form mental connections between items that co-occur, using exemplars found in language input. From this input, learners extract the rules of the language through cognitive processes common to other areas of cognitive skill acquisition. Since connectionism denies both innate rules and the existence of any innate language-learning module, L2 input is of greater importance than it is in processing models based on innate approaches, since, in connectionism, input is the source of both the units and the rules of language.
Other concepts have also been influential in the speculation about the processes of building internal systems of second language information. Some thinkers hold that language processing handles distinct types of knowledge. For instance, one component of the Monitor Model, propounded by Krashen (1982), posits a distinction between “acquisition” and “learning.”
According to Krashen, L2 acquisition is a subconscious process of incidentally “picking up” a language, as children do when becoming proficient in their first languages. Language learning, on the other hand, is studying, consciously and intentionally, the features of a language, as is common in traditional classrooms. Krashen sees these two processes as fundamentally different, with little
or no interface between them. In common with connectionism, Krashen (1982) sees input as essential to language acquisition. In his Input Hypothesis, he proposes that language acquisition takes place only when learners receive input just beyond their current level of L2 competence. He termed this level of input “i+1.” However, in contrast to emergentist and connectionist theories, he follows the innate approach by applying Chomsky (1981, 1986)’s Binding/Government theory and concept of Universal Grammar (UG) to SLA. He does so by proposing a Language Acquisition Device that uses L2 input to define the parameters of the L2, within the constraints of UG, and to increase the L2 proficiency of the learner. In addition, Krashen (1982)’s Affective Filter Hypothesis holds that the acquisition of a second language is halted if the leaner has a high degree of anxiety when receiving input. According to this concept, a part of the mind filters out L2 input and prevents uptake by the learner, if the learner feels that the process of SLA is threatening. As mentioned earlier, since input is essential in Krashen’s model, this filtering action prevents acquisition from progressing.
A distinction closely related to that made by Krashen (1982) between acquisition and learning is one between implicit and explicit linguistic knowledge. Learners gain implicit knowledge by processing target-language input without consciously giving attention to acquiring the forms and structures of the language. On the other hand, learners get explicit knowledge of a language when they process language input with the conscious intention of discovering the structural rules of the language. A distinction between the implicit learning involved in acquiring a first language (L1) and the mix of implicit and explicit learning that takes place in L2 acquisition has been one analytic route for understanding the virtually universal success of L1 acquisition versus the more limited success of L2 acquisition among adult learners (Hulstijn, 2005). Ellis (2005) has found empirical confirmation for the distinct constructs of implicit and explicit language knowledge. Some have used a declarative/procedural model to understand how language information is stored. This model is consistent with a distinction made in general cognitive science between the storage and retrieval of facts, on the one hand, and understanding of how to carry out operations, on the other. It states that declarative knowledge consists of arbitrary linguistic information, such as irregular verb forms, that are stored in the brain’s declarative memory. In contrast, knowledge
about the rules of a language, such as grammatical word order is procedural knowledge and is stored in procedural memory. Ullman (2001) reviews several psycholinguistic and neurolinguistic studies that support the declarative/procedural model.
Further, Bialystok and Smith (1985) make another distinction in explaining how learners build and use L2 and interlanguage knowledge structures. They argue that the concept of interlanguage should include a distinction between two specific kinds of language processing ability. On one hand is learners’ knowledge of L2 grammatical structure and ability to analyze the target language objectively using that knowledge, which they term “representation,” and, on the other hand is the ability to use their L2 linguistic knowledge, under time constraints, to accurately comprehend input and produce output in the L2, which they call “control.” They point out that often non-native
speakers of a language have higher levels of representation than their native-speaking counterparts have, yet have a lower level of control. Finally, Bialystok (1994) has framed the acquisition of language in terms of the interaction between what she calls “analysis” and “control.” Analysis is what learners do when they attempt to understand to be the rules of the target language. Through
this process, they acquire these rules and can use them to gain greater control over their own production.
Using Second Language Knowledge Structures Thinkers have produced several theories
concerning how learners use their internal L2 knowledge structures to comprehend L2 input and produce L2 output. One idea is that learners acquire proficiency in an L2 in the same way that people acquire other complex cognitive skills. Automaticity is the performance of a skill without conscious control. It results from the gradated process of proceduralization. In the field of cognitive psychology, Anderson (1992) expounds a model of skill acquisition, according to which persons use procedures to apply their declarative knowledge about a subject in order to solve problems. On repeated practice, these procedures develop into production rules that the individual can use to solve the problem, without accessing long-term declarative memory. Performance speed and accuracy improve as the learner implements these production rules. DeKeyser (1997) tested the application of this model to L2 language automaticity. He found that subjects developed increasing proficiency in performing tasks related to the morphosyntax of an artificial language, Autopractan, and performed on a learning curve typical of the acquisition of non-language cognitive skills. This evidence conforms to Anderson’s general model of cognitive skill acquisition, supports the idea that declarative knowledge can be transformed into procedural knowledge, and tends to undermine the idea of Krashen (1982) that knowledge gained through language “learning” cannot be used to initiate speech production.
Monitoring is another important concept in some theoretical models of learner use of L2 knowledge. According to Krashen (1982), the Monitor is a component of an L2 learner’s language processing device that uses knowledge gained from language learning to observe and regulate the learner’s own L2 production, checking for accuracy and adjusting language production when
Perhaps certain psychological characteristics constrain language processing. One area of research is the role of memory. Williams (1999) conducted a study in which he found some positive correlation between verbatim memory functioning and grammar learning success for his subjects. This suggests that individuals with less short-term memory capacity might have a limitation in performing cognitive processes for organization and use of linguistic knowledge.
Attention is another characteristic that some believe to have a role in determining the success or failure of language processing. Schmidt (1990) states that although explicit metalinguistic knowledge of a language is not always essential for acquisition, the learner must be aware of L2 input in order to gain from it. In his “noticing hypothesis,” Schmidt posits that learners must notice the ways in which their interlanguage structures differ from target norms. This noticing of the gap allows the learner’s internal language processing to restructure the learner’s internal representation of the rules of the L2 in order to bring the learner’s production closer to the target. In this respect, Schmidt’s understanding is consistent with the ongoing process of rule formation
found in emergentism and connectionism.
Restructuring Second Language Knowledge Structures Finally, some theorists and researchers
have contributed to the cognitive approach to second language acquisition by increasing understanding of the ways L2 learners restructure their interlanguage knowledge systems to be in
greater conformity to L2 structures. Processability theory states that learners restructure their L2 knowledge systems in an order of which they are capable at their stage of development (Pienemann, 1998). For instance, In order to acquire the correct morphological and syntactic forms for English questions, learners must transform declarative English sentences. They do so by a series of stages, consistent across learners. Clahsen (1984) proposed that certain processing principles determine this order of restructuring. Specifically, he stated that learners first, maintain declarative word order while changing other aspects of the utterances, second, move words to the beginning and end of sentences, and third, move elements within main clauses before subordinate clauses.
In addition, when learners experience significant restructuring in their L2 systems, they sometimes show what has been termed U-shaped behavior. For instance, Lightbrown (1983) showed that a group of English language learners moved, over time, from accurate usage of the “-ing” present
progressive morpheme, to incorrectly omitting it, and finally, back to correct usage. This is explained by theorizing that learners first acquired the “-ing” form as a chunk, second, lost control
of this form as their knowledge system was disrupted by expanding understandings of the tense and aspect systems of English, and third, returned to correct usage upon gaining greater control of these linguistic characteristics and forms. These data provide evidence that learners were initially producing output based on rote memory of individual words containing the present progressive morpheme. However, in the second stage their systems apparently contained the rule that they should use the bare infinitive form to express present action, without a separate rule for the use of “-ing.” Finally, their systems did contain such a rule.
In the preceding sections, I have introduced the principle ideas in the cognitive approach to second language acquisition. This approach has contributed to a greater understanding of how learners form internal language systems of information, use those systems in L2 processing, and restructure those systems as they gain greater L2 proficiency.