教学内容分析
This teaching period mainly deals with the grammar：the use of “it”．The impersonal pronoun “it” is used
frequently in English and has many different functions.“It” can be used in the subject or object position，to stand for an infinitive，－ing form or a clause.The impersonal pronoun “it” can be used to talk about time，distance，weather，etc.“It” can also be used for emphasis.
In this period we will focus on only part of its usages，that is，the use of “it” when the subject of a sentence is a clause，an infinitive，or the －ing form.
