大大的蚂蚁啊
什么时候用实意动词,什么时候用be,是看句子的具体意思的.有时候都可以用.比如he is a teacher.he works as a teacher.都能表示他是一个老师的意思. be 动词还会出现在进行时态当中和被动语态当中.he is having a meeting.(现在进行时）he was told to stay there.（被动）. have 作为助动词出现在完成时态当中,he has been a teacher for ten years. could 有两个意思,表示过去能够做某事he could skate when he was six. 表示委婉的请求 Could you pass the salt to me? would 有两个意思,表示过去将来 He said he would be a teacher . 表示委婉的请求 Would you please pass the salt to me 你说的即用情态动词或者助动词又可以用实意动词的情况是很常见的. 情态动词后面必须跟一个动词的原形,实意动词或be动词都可以. 助动词也必须和一个动词连用的.刚才上面所举的could would 的句子都是这种情况.
