（1）would是will的过去式，表示过去时间的意志、意愿、决心，用于各种人称。
They said they would help us.他们说他们愿意帮助我们。
I promised that I would do my best. 我承诺我决心尽最大努力。
（2）would表示说话人的意愿或向对方提出请求，语气比will婉转，仍指现在时间。
Would you like some bananas?你喜欢吃香蕉吗？
I'd like to see your new bike.我希望看看你的新自行车。
Wouldn't it be better to leave tomorrow?明天离开是不是更好？

（3）表示过去习惯发生的动作(与used to有区别，见used to)。
When he was there, he would go to that coffee shop at the corner after work every day. 他在那里时，他每天下班后都到拐角处那家咖啡店去。
The old worker would often go to the park to play chess.那位老工人过去常去公园下棋。
She would come to see me now and then.她时常来看我。
（4）表示推测。
That would be his father.那大概是他父亲。
You would be about 10 years old then.你那时大概10岁左右。