A healthy life Period 3 Grammar—the Use of “It”(1)
⑤it＋takes sb.some time＋to do sth.
⑥it＋seems/appears＋that clause
⑦it＋seems/appears＋as if clause
2.it作形式賓語的特殊用法。某些及物動詞或短語不能加賓語從句，此時須先用it作形式賓語，然后接賓語從句。此種用法常用于like，dislike，hate，appreciate，depend on，see to等后。如：
i hate it when people talk with their mouths full.
you may depend on it that they will support you.
i'll appreciate it if you close the door for me.
i like it in the autumn when the weather is clear and bright.
3.it 引起的幾個易混的時間句型
1)it's time for sb.to do sth.和it's(about/high) time that sb.did sth.(should do sth.)。例如：
it's time for us to go to bed.
it's(about/high)time that we went/should go to bed.
注意：it's (about/high) time that句型中，謂語動詞須用虛擬語氣，即用動詞的過去式或“should＋動詞原形”(should不能省略)。
(2)it/this/that is＋the first/second time＋that sb.has/have done sth.和it/this/that was the first/second time that sb.had done sth.例如：
this is the fourth time that she has rung you today.
it was the second time that i had visited the great wall last year.
(3)it will be long/hours/days/years before sb.do/does sth.和it was long/hours/days/years before sb.did sth.例如：
it will be two years before we meet again.
it was a long time before i got to sleep again last night.
(4)it is/has been＋years/days/weeks since sb.did sth.和it was years/days/weeks since sb.had done sth.例如：
—what was the party like?
—wonderful.it's years since i enjoyed myself so much.
it was years since i had began to learn english.
(5)it is/was＋具體時間點＋when clause。例如：
it's 6 o'clock when i go home from school every day.
it was five o'clock when they finished the job.
注意：在本結構中，when引導的從句是定語從句，具體時間點是先行詞。
step 7 summing up
try to help the students draw the following conclusions.
1.there are many sentence patterns in english with “it” in them.“it” has many functions.
2.when “it” acts as a subject or an object，the real subject or object can appear in the form of an infinitive，－ing form or a clause.the impersonal pronoun “it” can be used to talk about time，distance，weather，etc.
step 8 playing a game
1.get students to form groups of 6.
2.let students play the game “what is it？”.spend some time making up clues to identify several objects/illnesses/habits in this unit.then read your clues to your partner and see if he/she can identify them.choose the best ones to read to the class.
examples：
it is a bad habit for both males and females.
it is something you shouldn't start because you will be addicted to it.