时态\语态 主动 被动
一般式 to do to be done
进行式 to be doing
完成式 to have done to have been done
完成进行式 to have been doing
1) 现在时:一般现在时表示的动词,有时与谓语动词表示的动作同时发生,有时发生在谓语动词的动作之后。
He seems to know this.
I hope to see you again. = I hope that I'll see you again. 我希望再见到你。
2) 完成时:表示的动作发生在谓语动词表示的动作之前。
I'm sorry to have given you so much trouble.
He seems to have caught a cold.
3) 进行时: 表示动作正在进行,与谓语动词表示的动作同时发生。
He seems to be eating something.
4) 完成进行时:
She is known to have been wreaking on the problem for many years.