有it is time for sb.doing sth.和it is time for doing sth.这个句型吗?为什么?

英语中只有it is time for sb to do sth这个结构,没有it is time for sb.doing sth.
只有it is time for sth(名词/代词) 这个结构i,没有it is time for doing sth.
比如说：
It is time for me to go to bed./ It is time for bed