1. It作先行主語和先行賓語的一些句型
She had said what it was necessary to say.
2. 強調(diào)句型
It is not who rules us that is important, but how he rules us.
3. "All+抽象名詞"或"抽象名詞+itself"(very+形容詞)
He was all gentleness to her.