1.It’s the first time that……….(从句中用现在完成时)
It was for the first time that………(强调句，对状语for the first time进行强调)
It’s (high) time that……..(从句中用过去时或should do)
2.It’s the same with sb. / So it is with sb.表示某人也如此（用于前句中既有肯定又有否定或两个不同类的谓语动词）
3.…be about to do / be doing……when…….正要做/正在做……就在那时…….
4.A is twice / three times as +原级+as B
A is twice / three times the n. of B.
A is twice / three times +比较级+than B
5. It’s a waste of time / money doing / to do…
It’s no use / good doing………
It’s possible / probable / (un) likely that……….
It makes great / no sense to do……做某事很有/没意义
6.There’s no use / good doing…….
There’s no sense / point (in) doing……
There is no need for sth. / to do…….
There is (no) possibility that…………（同位语从句）
7.The+比较级…….., the+比较级………越…….., 越…….
注意：前半句为从句，用一般现在时代替将来时；
8.It seems / appears ( to sb. ) that sb…….在某人看来某人………
.= Sb. seems / appears to be / to do / to be doing / to have done……..
It seems / looks as if……….好象/似乎……..
9.It (so) happened that sb. ……..某人碰巧……..
= Sb. happened to be / to do / to be doing / to have done…..
10.It is said / thought / believed / hoped / supposed …….that sb………
=Sb. is said to be / to do / to be doing / to have done……….(注意：这种句型里如带动词hope则不能变成简单句，因为无hope sb. to do结构)