might 和could

might 和could

主要区别如下：
1. 用于疑问句表示请求时，一般只用Could,且可用于各人称。如：
Could you help me explain the difference between "might" and "could"?
Could I use your mobile phone a little while?
上句可用May代替：May I use your mobile phone a little while?
用Might也是可以的，但不常见。
2. could和might都可用在条件句中，表示假想的情况。表示“本来会、本来可以/能够”。例如：
If you tried you could/might do the work better. 如果你试试的话，准能把那项工作干得更好。
You could have met her if you had gone that way. 如果你走那条路的话，你准能遇见她。
此句中的could如改成might则表示：……，你也许能见到他。
They could/might have worked it out if they had asked me for help. 如果他们来向我求助的话，他们本能够做出来的。
He could/might have give the answer, but he refused to. 他本来能够回答的，但他拒绝这么做。
You were stupid to go skiing there — you could have broken your leg. 你真笨，竟会到那地方滑雪。你本来会摔断腿的。
上面的例句中用might则因其语气较轻而语意效果不甚理想。
在此场合，could和might的区别是could较might的可能性强。
3. couldn't be + 比较级句型不能用might代替。如：
Their lifestyles couldn't be more different. 他们的生活方式极为不同。
4. could和might都可用在表示“结果”的状语从句中，同样，could语气较重些。例如：
He expressed his ideas clearly so that the average person might understand. 他把他的意思清楚地表达出来，以便一般人能听明白。
5. might as well表示“不妨、可以、倒不如”，此时的might是不能用could代替的。例如：
We might as well look for some food now. 现在我们不妨找些吃的东西。
I expect I might as well be going. 我希望我可以走了。
Since it’s a fine day we might as well walk. 既然是一个晴朗的天，我们不妨步行。
We might as well have gone home as you suggested. 我们还不如按你建议的回家去呢。