need做实词和情态动词有什么区别

来源：百度知道 编辑：UC知道 时间：2024/05/27 09:46:35
The students were very glad that they_________their papers last weekend as the teacher was away on vacation.
C.needn't have handed in D.didn't need to hand in

答案是 D 。
为什么选 C 不行？

选C的话就是虚拟语气了

首先这里用have就是错的啊，need作情态动词的时候就和can什么的一样用法，就是后面只能接动词原形。作实义动词的时候就可以用need to do。

needn't是作情态动词时的否定式，don't need是作实义动词时的！