⑴ It';s time for + n.“该是(干)……的时候了。”例:
Boys andgirl, It';s time for class.
同学们,该上课了。
⑵ It';s time + (for sb.) to do sth. .表示“该是(某人)干……的时候了。”例:
It';s timefor you to clean theclassroom.
该是你打扫教室的时候了。
It';s time togo to school.
该去上学了。
⑶ It';s time + that clause时,that可省略,time可由high,about修饰,从句中的谓语动词有两种形式,或者用动词的过去式(be用were);或者用shoud+动词原形(should不能省略)。此句型为虚拟语气句型,表示“现在某人该做某事了”。含有该事早该去做而未做,现在去做似乎都为时已晚的意思。例:
It';s time (that)we went tobed.
我们该去睡觉了。
It';s high time that thearticle were published.
发表这篇文章是适时的。
It';s time you should docleaning.
你该去打扫卫生了。
⑷ It';s + the/序数词+ time +to do sth. 表示某人第几次做某事。例:
It is my first time to writeletter in English.
这是我第一次用英语写信。
⑸ It';s + the+序数词+ time+ that clause.也 表示某人第几次做某事。例:
It is my first time that I';veeven written letters.
这是我第一次用写信。
句型⑷ 句型 ⑸ 可以互换。

it's high time + doing sth
到该做……的时候了
16.8 It is(high) time that
It is (high) timethat后面的从句谓语动词要用过去式或用should加动词原形,但should不可省略。
It is time that the children went to bed.
It is high time that the children should go to bed.