You needn't ____(help) him. He can do it by himself. 用所给词的适当形式填空.请问填什么,为什么.

问题描述:

You needn't ____(help) him. He can do it by himself. 用所给词的适当形式填空.请问填什么,为什么.

填help
此处needn't 是用了need的情态动词用法,如果是使役动词用法,则应该是don't need
既然need此处是情态动词,则后面跟随着的应该是动词原型,所以填help
另外如果是使役动词用法,则正确形式是: You don't need to help him.