1、am用于第一人称单数现在时， I am afraid I am late already.恐怕我现在已经迟到了。
2、I often read some novels to kill time when I am alone at home.当我一个人在家时，我常通过读小说来消磨时光。
3、I am simply unable to call to mind his name.我实在想不起他的名字了。
4、I am anxiously awaiting your reply.我急切的等待你的回复。
