It is time to do sth. / for doing sth.

是时候该做某事了。

It(this , that)is the time for sb. to do sth.

是一种很常用的句式，意为“该到某人做某事的时间了。”

It is time for sb to do STH.

是某人做某事的时候了。

It is time (for sb) to do STH.

到了(某人)做某事的时间了。