句 式一．考点精讲1
陈述句肯定形式变否定形式类别方法示例谓语动词为 be 动词(am, is, are, was, were)在 be 动词后直接+ notHe is a student
→He isn’t a student
He was a teacher before
→He wasn’t a teacher before
谓语动词含有情态动词(can, will, must, should…)在情态动词后直接+ notHe can play football well
→He can’t play football well
谓语动词为实义动词，且没有情态动词、助动词在谓语动词(务必用动词原形)前+ don’t (原形用)；doesn’t (三单用)；didn’t (过去时用)I like apples
→I don’t like apples
He likes apples
→He doesn’t like apples
I liked apples before
→I didn’t like apples before
Tips: not 与其他词连在一起时，一般写为缩略形式，但 am not 不缩写
常见缩略形式如下：is not = isn’t are not = aren’t was not = wasn’t were not = weren’t do not = don’t does not = doesn’t did not = didn’t have not = haven’thas not = hasn’t should not = shouldn’t must not = mustn’t need not = needn’tcan not = can’t will not = won’t2
陈述句变一般疑问句类别方法示例谓语动词
