解题思路： 如下
解题过程：
1. can (could)
1) 表示能力,could主要指过去时间。例如:
① Two eyes can see more than one. 两只眼比一只眼看得清。
② Could the girl read before she went to school? 这女孩上学前能识字吗?
2) 表示可能(理论上或是逻辑判断上)。例如:
① He can’t (couldn’t) have enough money for a new car. 他不可能有足够的钱买新车。
② You mustn’t smoke while you’re walking around in the wood. You could start a fire. 在林子里走时勿吸烟,那样可能会引起火灾。
3) 表示允许。例如:
① Can I have a look at your new pen? 我可以看一看你的新钢笔吗?
② He asked whether he could take the book out of the reading—room. 他问他可不可以把书带出阅览室。
4) 表惊异、怀疑、不相信等态度。主要用于否定句、疑问句或感叹句中。例如:
① Where can (could) they have gone to? 他们会去哪儿了呢?
② How can you be so careless? 你怎么这么粗心?
5) 比较委婉客气地提出问题或陈述看法。例如:
① Can (Could) you lend me a hand? 帮我一把好吗?.
② I’m afraid we couldn’t give you an answer today. 恐怕我们今天不能给你答复。
2.would
1) 表意愿。例如::
① They would not let him in because he was poorly dressed. 他们不让他进去因为他衣着破旧。
② I said I would do anything for you. 我说过我愿意为你做任何事。
2) 表委婉地提出请求、建议或看法。例如:
① Would you mind cleaning the window? 请把窗户擦一下好吗?
② They wouldn’t have anything against it. 他们不会有什么反对意见。
3) 表过去反复发生的动作或过去的一种倾向。例如::
Every time she was in trouble, she would go to him for help. 她每遇到麻烦都会向她求助。他告诉我盒子打不开了。
例题1 Peter ____ come with us tonight, but he isn't very sure yet.
A. must B. can C. may D. will
分析：这道题是并列句，虽然第一分句子成立，即 Peter今晚愿意跟我们来，但与第二个分句不一致。这里isn’t very sure yet很重要，说明还没有定下来。如果对“not sure”这个暗示给予足够的注意，就会选择C，may表示可能。如果用can来表示“可能”，要放在疑问句或否定句中。而must表示“必须”，此处不合题意，故被排除。此题答案是C。
例题2 When he was there, he ___ go to that coffee shop at the corner after work every day. 【解析】would指过去习惯性的动作。
例题3：You _____ be tired—You’ve only been working for an hour.You _____ be tired（你不可能很累），can’t 表示“不可能”答案为C.
A. must not B. won’t C. can’t D. may not
分析：根据后半句You’ve only been working for an hour.（你才刚干了一个小时）说明
A. would B. should C. had better D. might
最终答案：略
