Related researches in China started later。 Here I cite two cases。

Xin Ke and Zhou Shuli made an investigation on 81 postgraduates who studied in Northwestern Polytechnical University。 By analyzing the impact that primary school English learning brought about on postgraduates’ verbal scores and comprehensive scores, they obtained the correlation between postgraduates’ English performance and English curriculum in primary school which led to the following conclusions。 If children start to learn English from Grade 4 or Grade 5, then a considerable number of them will be likely to achieve relatively high level of oral and comprehensive competence in adult stage (undergraduate or postgraduate)。 They gave advice like parents and society should let children expose to English as soon as possible if their ultimate objective is that children can speak English as well as native speakers。 (Xin and Zhou 2006)

Domestic educators Chen Baoguo and Peng Danling made a relatively comprehensive review about CPH’s concept, evidence, genesis and research achievements on the basis of previous studies, indicating the revelation on language education。 They summarized following harvests of language acquisition critical period researches: 1。The language acquisition process starts from early infancy。 2。 Starting learning language after 5 years old, the language development is imperfect。 The later one starts learning language, the lower his efficiency of language acquisition is。 3。 There is some relation between language acquisition critical period and level of brain plasticity or lateralization。 4。 Critical period exists in second language learning, which remarkably manifests that the littler learners are, the easier they pronounce the second language correctly。 When it comes to grammar, this theory needs further evidence at present。 5。 Maybe there is more than one critical period in language learning acquisition。 That is to say, different language components probably have different critical periods。 In addition, they concluded some enlightenment to education。 For example, if condition permit, second language education should start sooner (e。g。 Grade 1) and emphasize learning intonation in the beginning。 Educators should take an active part in creating an ample language environment for students。 (Chen and Peng 52)来*自~优|尔^论:文+网www.youerw.com +QQ752018766*

All in all, comparing two distinct standpoints of pros and antis, people gave supporters more applause than protesters。 After all, lots of examples and theories of sustainers confirmed the existence of critical period while when it came to opponents’ ideas, evidence seemed a little weaker。 Anyway, time before puberty is the most critical during the critical period for those learners of both first language and second language。

The summary of above researches, including both foreign and domestic cases, animal and human being cases, normal and disabled personal cases, can be regarded as comprehensive。 However, there are relatively less local empirical studies in China。 Domestic researchers basically summarize and discuss previous theory results, lack of living investigation based on national conditions, even regional conditions。 Besides, biological studies will inevitably be interfered by many uncontrollable subjective and objective elements so people can take advantage of developed science and technology to explore what changes will brain nerve tissue make and how the function of nerve tissue and input of external environment interact each other in language acquisition critical period。