時(shí)態(tài)語態(tài) 主動(dòng) 被動(dòng)
一般式 to do to be done
進(jìn)行式 to be doing
完成式 to have done to have been done
完成進(jìn)行式 to have been doing
1) 現(xiàn)在時(shí)：一般現(xiàn)在時(shí)表示的動(dòng)詞，有時(shí)與謂語動(dòng)詞表示的動(dòng)作同時(shí)發(fā)生，有時(shí)發(fā)生在謂語動(dòng)詞的動(dòng)作之后。
He seems to know this.
I hope to see you again. = I hope that I'll see you again. 我希望再見到你。
2) 完成時(shí)：表示的動(dòng)作發(fā)生在謂語動(dòng)詞表示的動(dòng)作之前。
I'm sorry to have given you so much trouble.
He seems to have caught a cold.
3) 進(jìn)行時(shí)： 表示動(dòng)作正在進(jìn)行，與謂語動(dòng)詞表示的動(dòng)作同時(shí)發(fā)生。
He seems to be eating something.
4) 完成進(jìn)行時(shí)：
She is known to have been wreaking on the problem for many years.