would是will的过去式形式，加not后，就构成了否定式，所以说wouldn't是过去将来时，即以过去为出发点将要发生的事情。
而won't是will加not的缩写形式，它表示的就是一般将来时，即以现在为出发点，将来有可能发生的事情。
一、wouldn't
英 [ˈwʊdnt] 美 ['wʊdnt]
不会
扩展例句
1、You wouldn't catch me in there, I can tell you.
我可以告诉你，你永远别想在那里看见我。
2、You wouldn't remember me. I was in another group
你不会记得我。我那时在另外一组。
3、We are not normal like everybody else. If we were they wouldn't be oppressing us.
我们跟其他正常人不一样。否则，他们就不会压迫我们了。
4、If I were you, Mrs Gretchen, I just wouldn't worry about it
要是我是你，格蕾琴夫人，我一点都不会担心。
二、won't
英 [wəʊnt] 美 [woʊnt]
将不，不会（=will not）
扩展例句
1、No, no, no. This won't do. Someone is off-key.
不，不，不，这怎么行，有人唱走调了。
2、I won't go out today; I'll stay in and work.
今天我不出去了，我留在家里工作。
3、If it rains tomorrow, we won't go.
明天要是下雨，我们就不去了。
4、It's outrageous, and we won't stand for it any more.
这太不像话了，我们再也不能容忍下去了。