试着说出It的用法。

It's surprising that he should ask me such a difficult question．

It做________主语；指代________从句。

试着说出It的用法。

It's no use crying over spilt milk．It做________主语。

试着说出It的用法。

We published it that we had won the football game．

It做形式________；指代________从句。

试着说出It的用法。

You may find it exciting working here．It做形式________；指代________短语。

下列词汇为本单元出现的考纲词汇的派生词。填填看，掌握了它们的用法了吗？

1．New furniture is too ________; we'll use the old pieces．

2．The railroad connects two cities, ________, New York and Chicago．

3．He surrounds himself with attractive, ________, or well-known people．

4．The steam engine is a ________ invention．It marks the coming of a new era．