这篇关于语言习得的，我贴在田老师“我所进行的双语教育”那一楼，也顺便贴到这里供大家参考：
关于语言习得， 以下是以英语为母语的小孩子的语言习得的规律及发展顺序，对照起来，田田的英文已很超前啦！
里面也提到多大的小孩子学外语不会有口音，所以正像HQ1966版主曾主张的，学英语一定要趁早啊！
Language acquisition
Language acquisition refers to the child’ acquisition of his mother tongue, i.e. how children come to understand and to speak the language of their community.
The beginning of language
The basic essentials of the first language of acquired in the short period between the ages of 1.5years and 4 years. This is called the critical period for first language acquisition. Some of the most complicated constructions, e.g. passives, may not be fully mastered until about ten years of age. Of course, language learning proceeds throughout life as vocabulary increases, and skills in the appropriate use of language are continually refined.
Stages in first language acquisition
A. Between birth and around six months children produce a series of sounds and this is called the “babbling period”.
B. Around eight months—now babbling is replaced by syllables, e.g. [mama]
C. One year—the child attempts to carry out simple commands. He can also speak a few words, e.g. [bab]—baby.
D. Eighteen months—this age is usually cited as the onset of speech. His vocabulary consists of between three and fifty words, e.g.[d^k]—duck.
E. Two years—The child can now name most things which are familiar to him in his surroundings. He often utters two-word phrases which he has not imitated and which, therefore, is his own creation, e.g.—more juice.
F. Two and a half years—The child seems to understand almost everything said to him.
G. Three years’—The child now has a vocabulary of about a thousand words. The grammatical complexity of the utterance is about equal to that of colloquial adult speech.
H. About four years—the child has now mastered the essentials of his mother tongue.
Age and native language acquisition
Children soon outgrow their ability to acquire language with little effort, and this is realized by adults who try to master a language in addition to their mother tongue. Whether or not a child will speak a foreign language with an accent depends largely upon the age at which he learns the second language. A child who enters a foreign language speech community by the age of three or four learns the new language rapidly and without the trace of an accent. Around the age of puberty(10-13), the child loses his ability to learn a second language without an accent. Thus, there is a critical period for first language acquisition, and for acquiring a language with native-like control.
Common order in the development of language
In English, as in all languages, the sound(phonology) and the structures(grammar) develop in regular stages for all children. This allows us to make certain generalizations about the learning of phonology and grammar.
In phonology, for example, certain sounds will be produced (i.e. spoken) before others. So consonants such as [m] and [d] will be produces before [s] or [z].
In grammar, all children begin with simple one-word utterances, e.g. Mama! And proceed in regular stages to more complex sentences.
Different rate of language development
Although there is a common order in first language acquisition, this does not mean that all children learn at the same rate.
It is generally believed that by the age of 8, a child has mastered the complex grammatical structure, such as the complement construction:
