2。2 Previous studies at home and abroad

Wang Dawei points that unnatural input influence the second language learning greatly and he also puts forward “all input mode” of a large number of input (Wang 43)。 Zhang Huanxiang and her research team find that the full use of different kinds of language input especially the use of teachers’ feedback in the class situation can improve the foreign language classroom efficiency (Zhang 15)。 Zou Weicheng argues that the key from language input to language intake is the chance (Zou 5)。 Luo Lisheng points that Krashen’s “i+1” theory was founded on the basis of language acquisition and second language acquisition (Luo 13) 。 However, in the process of foreign language teaching in China, the environment, the language of contact conditions of foreign language learners have undergone great changes。 论文网

However, from the perspective of language learning, Krashen's input hypothesis can still produce some inspiration for foreign language teaching, mainly in the following aspects: (1) Krashen's input hypothesis makes people understand theoretically in the foreign language teaching process, teachers should pay full attention (including both in-class and extra-curricular), and provide a more authentic language use environment for learners in the process of language input。 (2) Krashen's input hypothesis points that we further recognize that learning a foreign language is more dependent on the visual language input, i,e。 reading。 Visual input should be enhanced, such as the updating of the input content concept and the variety of input forms。 (3) Foreign language teaching can be in a specific learning stage following “i + 1” input principle: first, the selection of teaching materials; Second, difficulty of the language teachers use in the class。 Wang Xiaoning argues that Krashen's input hypothesis exaggerates the importance of language input, simplifies the process of language acquisition, ignores the influence of social environment and social factors on foreign language learning, and is difficult to verify in practice and needs further development and improvement (Wang 6)。

In order to further study this problem, Schmidt introduced the concept and method of experimental psychology into the study of second language acquisition and proposed the “Noticing Hypothesis” (Schmidt 17)。 He argues that “attention is a necessary and sufficient condition for translating input into intake”。 Although attention is still questioned in the necessity of second language acquisition, its promotion of second language acquisition has been demonstrated by a number of empirical studies。

Gass depicts a flow chart of the human brain mechanism acquisition language from the perspective of cognitive psychology and he considers language acquisition to be a very complex process that includes the process the learner transforms the input into several stages of the output process and distinguishes the language input into the language input that is noticed or perceived by the language input and the language that is understood。

Ellis proposes the Model of Instructed SLA (Ellis 166)。 He argues that input of declarative knowledge should not be overlooked and it helps to draw learners' attention to the input language form and can be converted directly into procedural knowledge by repeated practice。 It is also as a monitor that helps to improve learners the quality of language input。

Skehan also proposed a “three-stage task-based teaching model” (Skehan 6)。 Through the second language communication, it can promote the awareness and proficiency of the declarative knowledge of the speaker。 These theories have a good guiding significance for the second language classroom teaching。 Krashen's input hypothesis theory is controversial in the world。 Krashen’s “input hypothesis” emphasizes the decisive role of the comprehensible input, but the output of the second language acquisition has no effect。 This view immediately aroused the strong question of many scholars, of which the greatest impact is Swain。 He put forward comprehensible output hypothesis。 In his study of French immersion in Canada, Swain found that although the native English students accepted a large number of "understandable inputs", the French proficiency of these students did not reach the ideal effect。 Swain attributed the reason to their lack of language expression training, that is, language output。 Therefore, Swain concludes that it is understandable that input has a great effect on second language acquisition, but it is not enough to develop the level of the second language learners (Swain 18)。 From the input point of view, the teaching content should take into account the degree of acceptance of learners, and the appropriate increase in the number of understandable input, but also should pay attention to its quality improvement。