Second language acquisition as an independent subject was probably formed in the late 1960s and early 1970s. Second language acquisition research is a multidisciplinary cross-cutting study. Researchers study how learners learn another new language system after mastering their mother tongue from the perspectives of linguistics, psychology, pedagogy, and sociology (Dai Weidong 2008). With the in-depth development of the study of second language acquisition, its research methods also show interdisciplinary and diversified characteristics, and different research methods have produced different research results, which has weakened the verifiability and contrast between the various studies. Therefore, reviewing and summarizing the research methods of second language acquisition is of great significance to promote the scientific and effective development of second language acquisition research.
After decades of development, the study of second language acquisition has drawn two conclusions that second language acquisition is highly systematic and variability in second language acquisition. Systematic means the nature of the different stages that learners of second language acquisition experience in their second language acquisition. It is called a route of development in linguistics. To a large extent, this development approach maintains a relatively independent and independent relationship with the learner's mother tongue and their learning environment (whether in the school classroom or in a natural acquisition environment). The variability of second language acquisition usually means that in the process of second language acquisition, both the speed of learning the second language and the results of learning are different from person to person, some people always learn better and faster than others.
1. Historical Review of Research Methods.
Dai Weidong (2007) statistical analysis shows that since the 1980s, the research methods of domestic second language acquisition mainly use quantitative research; the research materials are mainly written materials, and the research on oral materials is seriously insufficient. Wen Qiufang et al. (2004) introduced the latest progress in the research methods of second language acquisition. First, after entering the 21st century, the micro-change method was introduced into the field of second language acquisition. Its advantages are that it can reveal the trajectory and mechanism of second language acquisition. Second, since the mid-1990s, the Contrastive Interlanguage Analysis has become a new method in the study of second language acquisition. Micro-level method research mainly involves the effectiveness methods of learning strategy research (2004), evaluation methods of empirical research on second language acquisition, and important indicators and principles for evaluating research quality (2002). Zhou Guanglei and Cai Jinting (2007) pointed out that grammatical judgment is a relatively complicated research method, involving many factors, which leads to its reliability and validity being affected by many factors, but it has outstanding advantages compared with other meta-language research methods, so it is necessary to improve this research method from two aspects of reliability and validity on the basis of recognizing its limitations.
We use the following steps to search Chinese and foreign journal databases respectively to objectively show the research status of "Second Language Acquisition Research Methods" in the world: (1) Determine the Chinese and English search terms and their extended synonyms and second language or language or foreign language or English; acquisition or learning; research method. (2) Clarify the logical relationship between technical terms, and formulate a search formula: Different search terms are connected by "*" or "and", synonyms and synonyms are connected by "+" or "or". (3) In order to ensure the accuracy and recall of the search, the search formula is repeatedly adjusted according to the search results to obtain the Chinese and English search formulas that are most suitable for the research literature search: (second language + second language + language + foreign language + English) 2014 (General Serial No. 164) (research method) (second language or language or foreign language or English) and (acquisition or learning) and (research method *), In a foreign language database refers to a truncation character. In this search formula, "*" means that all words with stem "method" can be searched. In the comprehensive foreign language journal database EBSCOhost, we performed a high-level search of the data from 1984 to 2013 with the title field, and there are 12 papers on research methods of second language acquisition from well-known foreign academic journals. There are 25 related papers in the full-text database of Chinese academic journals, of which 10 are from foreign language core journals. It can be seen that the research methods in the field of second language acquisition at home and abroad are paid more attention to but are rare. In addition, according to the statistical analysis of the titles, keywords, and abstracts of 37 academic papers, about 65% of the papers are research methods that focus on one aspect of second language acquisition. About 35% of the papers more comprehensively summarize the research methods of second language acquisition, which shows that a comprehensive review of second language acquisition research methods is rare. In addition, the article "Research Methods in Second Language Acquisition for 35 Years: Review and Thinking" (Wen Qiufang, Wang Lifei 2004), which has the highest citation rate index in this type of paper, summarizes the universal quantitative and qualitative research methods in social science research. Based on its own research characteristics and research focus on the main research methods, It is helpful for the second language acquisition researchers in China to obtain theoretical and practical research references. llis and Barkhuizen (2005) divide learner language samples into non-language use samples, learners' oral or written language samples, and learner reports on their own learning, and then introduce methods of collecting and analyzing language samples. Litosseliti (2010) divides second language acquisition research into observational, experimental, and quasi-experimental research. Mackey and Gass (2012) believe that the research framework of second language acquisition can be mainly divided into linguistic, psychological, and sociological frameworks. Wu Xudong (2002) divided research on second language acquisition into exploratory, descriptive, and explanatory categories according to the research purpose. Wen Qiufang and Wang Lifei (2004) divided the research of second language acquisition into quantitative research and qualitative research according to research methods. In general, there are two ideas were used by scholars to classify the second language acquisition research methods: (1) the quantitative, qualitative and mixed research methods used in universal classification of social science research generally (2) combined with the characteristics of the second language acquisition research itself to classify the methods based on the research perspective and object.
2. Current Application and Development Direction of the Research Methods of Second Language Acquisition in China
The review of second language acquisition research methods based on different research perspectives are not only helpful to grasp the overall situation of international second language acquisition research development, but also to reveal the current situation of second language acquisition research in China, and further promote the development of domestic second language acquisition research. Therefore, we summarize the current situation of the application of second language acquisition research methods in China, and put forward corresponding development suggestions for research methods.
(1) The majority research method on second language acquisition is qualitative research and research on the combination of the two is lacking (Yin Liwen, 2011). From the point of view of research methods, both qualitative and quantitative research need to be improved, which shows that all research methods are not good or bad and are not exclusive to a certain research area. In the future research of second language acquisition, researchers can choose and combine different research methods for different research problems and research objects, and adopt multi-party verification to promote the development of second language acquisition research.
(2) Many second language acquisition research designs lack a pilot study link. From the previous analysis of different research methods, it can be seen that there are unavoidable omissions in the language sample collection process. For the sake of rigor, before starting the formal research, researchers can through small-scale experiments to verify the feasibility and adequacy of this research scheme and make adjustments to ensure the subsequent research. Can be smoothly carried out.
(3) Replicated second language acquisition research is rare. Different conclusions will be drawn due to different research methods and research conditions, which makes the discussion of certain research issues impossible to form a conclusion. Of course, this is related to factors such as the complexity and research methods of the second language acquisition research problem itself. Therefore, repetitive verification in the field of second language research is necessary to find convincing and generally accepted answers.
(4) Many second language acquisition research methods are based on foreign research designs. Whether they are applicable to our foreign language learners and what localization issues will need to be further studied. Chinese second language acquisition research needs to design appropriate test scales based on the actual situation of learners in China to create second language acquisition research methods and theories in line with China's national conditions, which is the direction and goal of the researchers of second language acquisition in China for a long time in the future.
3. The Enlightenment of Second Language Acquisition Theory in Teaching
The second language acquisition theory plays an important guiding role in our foreign language teaching. The general grammar model believes that learning comes from rich and natural information input, and that the learning process of second language acquisition and first language acquisition is very similar, and children do not need grammar learning to be fluent in their native language. Common grammar patterns arise from applying children's mother tongue learning and understanding to second language acquisition; The communicative teaching mode is a new one summarized by the language teachers in the teaching failure of the applied grammar, the translation mode and the listening and speaking method, because they think that the old mode ignores the cultivation of the need for real life communication.
The main theoretical basis of the grammatical translation model is that the goal of learning a foreign language is to read foreign materials and literature, so as to promote the development of the mind by learning a foreign language. This teaching method focuses more on reading and writing. Learners learn vocabulary mainly through the methods of bilingual interpretation of vocabulary lists and dictionary. Sentences are the most basic unit of teaching and language practice. The classroom teaching mainly focuses on the translation of the source sentences and the target sentences. When teachers teach grammar, they first demonstrate through examples, then teach specific grammar rules, and then let them practice through writing and other methods. Chinese teachers usually do not use English directly in the teaching process, and often use Chinese to explain specific words, sentences and grammar. This method is mainly for students to master grammar faster, improve vocabulary, and take exams. Grammar learning is mainly that the learner first reads the text, then the teacher conducts specific teaching of grammatical structure, and translates word by word, and then the learner applies the grammatical structure and vocabulary mastered in the classroom to reading exercises and written exercises.
Cognitive and information processing models or association models view learning as the reinforcement and consolidation of interconnected information. It also enhances the automation of routine programs. Therefore, the learner plays a central role in the process of acquisition learning. The transmission and use of information, the interaction between teachers and students, and whether the students apply what they have learned are very important factors.
The behavioral teaching model that prevailed in the 1960s and 1970s believed that people's language learning was a teaching model based on the habit-formation behaviorist perspective. Therefore, the learning of language have to form new habits through continuous training. This is the Audio-lingual method. Communicative Language Teaching believes that language learning needs to be acquired through communicative activities. Therefore, teachers need to encourage students to actively participate in classroom discussions in teaching and design more language activities such as role-playing, so that students can move the theory of classroom learning into practice.
The main viewpoint of the teaching model of language communicative competence is that communicative activities promote learners' language learning; meaningful language activities for learners have a positive role in promoting language learning. This teaching mode is very different from the grammar translation method. The important characteristics and advantages of communicative teaching method and communicative competence training are its action orientation, language contextuality, and the combination of learner needs. Teachers can teach different expressions of the same sentence in different situations. For example: "Why don’t you open the window?" May express "Ask," "Suggest," or "Order" in different situations.
Domestic scholars who study the combination of second language acquisition and foreign language teaching have discussed the enlightenment of mainstream theories of second language acquisition on language teaching in China, the application of the results of second language acquisition research in language teaching, and the relationship between theory and application. From the micro perspective, this paper explores the inspiration and guiding significance of second language acquisition theories and models for the teaching of various language skills. Based on the theory of second language acquisition, Dai Weidong and Shu Dingfang (2001) systematically explored the theoretical significance of several important aspects such as factors affecting foreign language learning, comparative analysis, error analysis, interlanguage and communication strategies, and their implications for foreign language teaching. Inspired by several influential theoretical models of second language acquisition, Mr. Wang Chuming tried to design a theoretical model of foreign language learning for Chinese students based on the learning characteristics and learning environment of our foreign language students. Chinese scholars also realize that there are obvious differences in the learning of "second language" and "foreign language ", whether in language environment, language input, learners ‘learning motivation, affective factors, cognition basis, mastery degree and learning goals. Confusion between these two different concepts will confuse the completely different characteristics of second language teaching and foreign language teaching. Regarding the role of formal classroom teaching on language acquisition, Liu Runqing believes that a language environment provided indirectly by formal teaching is beneficial to achieving a higher level of language, because only by paying attention to the language form can we begin to process and acquire language. Hu Zhuanglin believes that under the circumstances that college English learning in China is still dominated by classroom teaching, English acquisition should be flexible, which can be divided into full acquisition, instructional acquisition and self-learning acquisition. Teachers should guide students 'self-study acquisition so that they can help improve learners' English proficiency. Regarding the relationship between second language acquisition research and language teaching, some scholars believe that although second language acquisition research cannot provide direct and useful results for teaching, it can deepen our understanding of learning activities and teaching activities; the study of second language acquisition and language teaching practice is a complementary relationship. The former provides the latter with principles and theories, and the latter provides the former with a field of practice, conducts action research, and provides empirical evidence, resulting in more scientific research results.
The second language acquisition research method not only plays a vital role in the second language acquisition research, but also has a demonstration and guidance significance to the language teaching. Second language acquisition research method is to undertake language acquisition theory and language teaching Practice Bridge. If language teachers can understand the theory of second language acquisition and pay attention to the research methods and practice modes behind the theory, it will be more helpful to use scientific methods to conduct research on second language acquisition in teaching and solve practical problems in foreign language teaching. Only when language teachers explore and master the characteristics of foreign language learners' language learning process, psychological process, and education process, can they find the most suitable foreign language teaching mode according to the learning rules and improve the efficiency of foreign language teaching.
On the other hand, the study of second language acquisition has not been introduced in China for a long time, and foreign theories need to be continuously verified in our foreign language teaching environment. Secondly, we should soberly recognize the existing gaps and deficiencies. Therefore, a study of second language acquisition in close combination with the characteristics of Chinese learners will help to understand the objective laws of Chinese students' foreign language learning and reveal the cognitive psychological process of foreign language learning. It helps us to establish correct guiding principles of foreign language teaching, and helps to solve many problems that are common in our foreign language teaching, thereby improving our foreign language teaching level as a whole, and developing our foreign language learning theories and foreign language teaching theories.
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作者简介：叶琦，男，1988年生于山西太原，现居北京海淀。2014年毕业于中国传媒大学新闻与传播专业，硕士研究生。2018年任中华文化促进会朗读专业委员会理事，讲师职称。主要从事中国播音学、外国语言学及应用语言学方向的传播教育工作。