# 情态动词的否定 情态动词+not+动词原形 ``` He can't sing an English song. He may not know her. He mustn't go there. He doesn't have to go there. ``` # 情态动词的提问 情态动词+主语+动词原形 ``` Can he sing a English song? -Yes,he can./No,he can't. Must he go there? Yes,he must./No,he needn't. Does he have to go there? Yes,he does./No,he doesn't. ```