When the learners receive language materials, they can only reduce their psychological barriers, and let them consciously process the input language information in order to ensure higher information absorption。 Previous studies have shown that anxiety, inferiority and conflict affect the quality of learning。 Only those learners who do not know and want to know can stimulate their interest in learning。 Therefore, whether it is classroom teaching or extracurricular learning, the input of language materials should be meaningful and interesting。 

3。3 Not Grammatically Sequenced 

The quantity of language input is the premise and foundation of language acquisition。 A large amount of language input can be used in language acquisition。 In the process, learners naturally absorb many useful language materials and language knowledge; otherwise, language acquisition is just empty words。

Acquisition means unconscious。 However, the process is the primary way to obtain the language; and learning is conscious purposeful process。 Through the study can only get the relevant language knowledge which does not lead to access to language。 Learning in the process of mastering the language only plays the role of test and correction。 Consciously learning the language knowledge cannot be applied to the real life, and only through the acquisition of talent really get the language of effective communications文献综述

Learners in the reception of language materials, should reduce their psychological barriers, in order to ensure a higher rate of information absorption。 Studies have demonstrated that anxiety, inferiority, conflict and other emotions will affect the quality of the acquisition。 Only those learners do not know and want to know things to stimulate their interest in learning, so, whether it is classroom or extracurricular learning, the input of language material will be meaningful and interesting。 In this way, the learning will end up with "knowing about" the second language (Krashen 335)。 Learners may not know the inner meaning of the second language。 Krashen holds the view that the acquisition is a process which is more important。

3。4 Sufficient Input 

Krashen pointed out that in the process of language input should follow the principle；The language information entered in the input process should be true。 Language acquisition，only in the actual context can be produced。 In the territory, language communication can exclude the interference of the mother tongue, to the sound, shape, meaning and other aspects of the same, which reflects the effective meaning。 Principle can make learners no longer consciously consider the language，no longer spend more time and effort on the two languages for comparison and translation, it is easier for learners to achieve better learning outcomes。

Krashen argues that language acquisition is important enough to have a sufficiently understandable input, and learners do not need to acquire a language in strict accordance with the order of acquisition of grammatical procedures, since language acquisition is passed in a natural environment。 Communication is their main purpose to acquire language。