would、将要 （语气是一种客观,陈述性的）
should、需要（语气 强,主动）
could 可能,可以 （强、主动）
might 可能、或许（弱,猜测）如果有一道题What do you think of his suggestion that we________the work before lunch?A：would finish；B：should finish；C：could finish；D：might finish；这道题考察的是哪个知识点。如果有一道题What do you think of his suggestion that we________the work before lunch?A：would finish；B：should finish；C：could finish；D：might finish当然选B。What do you think of his suggestion that we should finish the work before lunch?你认为他关于我们需要在午餐之前完成这项工作的建议如何？【we should finish the work before lunch】【我们应该（需要、必须）在午餐之前完成这项工作】是建议，其他的都不通顺。建议主动去做某事，只能是should 。