2。 Literature Review

In order to expand junior students’ vocabulary, both teachers and students should shoulder their own responsibilities to teach and learn English vocabulary。

2。1 Vocabulary teaching and vocabulary learning

Vocabulary teaching and vocabulary learning needs the cooperation between teachers and students。 Both of them should obey the following three principles which are relevant to “i+1” theory。

 2。1。1 The principle of “step by step”来自优I尔Q论T文D网WWw.YoueRw.com 加QQ7520~18766

 Apparently, there is no distinction between English vocabulary, but in fact, the frequency of use of English vocabulary is very different。 In teaching, teachers should guide students to master the relatively high frequency of the core words, and then is the frequency of the lower vocabulary, step by step mastering the use of vocabulary。 In addition, a word often has a variety of meanings and collocations。 Some students try to remember all the meanings and all the collocations of a word once and for all。 In fact, this method explains “i + 2” if it is written by Krashen's language input theory。 Trying to remember all the meaning or most of the meaning just one time, which has been a sudden jump to the “2” language input on the basis of the original vocabulary。 The result is that the last even a sense or usage can not be remembered。 Therefore, when students remember a new word, you should first remember one or two kinds of meaning and usage, and then remember the other meaning and usage, expanding the vocabulary according to the principle of “i+1” theory。

2。1。2 The principle of the context 

Krashen’s “i + 1” formula is extremely general, and he does not explain in detail what exactly “i” is and does not specify what “1” is。 In fact, because of the high degree of generalization of the theory, he can not explain specifically。 For vocabulary learning, “i” can be seen as the context that a learner can understand including sentence context, paragraph context, chapter context, passage context and so on。 In short, vocabulary learning should be done in a specific context。 For example, it would be better to put a new word in a sentence or in a paragraph because the new word is “1”, that is, it is slightly higher than the learner's existing level, and the language that can be understood happens to be “i”。 The combination of the two is followed by the “ i + 1” principle。 Learning vocabulary in context seems to increase the burden of learner information input, but in fact, it is more able to strengthen the brain's memory, and the words are more credible, while students can understand the specific usage of the vocabulary。 This is why the word can not be memorized through the vocabulary, because this vocabulary input has completely exceeded the “1” difficulty range。

2。1。3 The principle of repetition

In fact, we should understand Krashen's “i + 1” theory as a dynamic process, that is, the language level should be improved from “0” to “i”, and then to “i + 1”, then to “i + 1” continuous dynamic process, the language level continues to improve like the snowball。 In other words, a higher level of language skills “i” is actually a shallow “i + 1”, only the level of foreign language can be improved。 However, given the special memory patterns and storage capabilities of the human brain, it is almost impossible to remember the word forever after a one-time memory of a word, and people are always remembering, forgetting, remembering, and forgetting in the process of a final grasp of the vocabulary。 Researchers point out that human forgetting generally follows the principle of “first fast and slow”。 Thus, a one-time memory may allow us to briefly increase the level of vocabulary to the level of “i + 1”, but after a period of time because of the law of forgetting, and it is likely to return to the original "i" level。 This requires us to continue to repeat the vocabulary to learn to consolidate the results of “i + 1”。