expletive it / anticipatory it
Dummy it, and it that points ahead to a clause.
Expletive it is a dummy subject. It fills the subject slot and does not point back to a noun: It is raining. It is a long way. It is too late. Expletive here means a filler word, not a swear word. Anticipatory it is that same dummy it when the real content comes later: It is clear that the pump failed. The it holds the place of the clause that follows. Both are standard.
Examples
Use It is late.
Use It is clear that the pump failed.