1 陈述句 含义：用于陈述事实和观点的句子。陈述句包括肯定结构和否定结构。 This is a desk.（肯定结构） He can sing and dance.（肯定结构） He doesn’t have a computer.（否定结构） There aren’t any pictures.（否定结构） 肯定句变否定句： 1. be 动词的否定式 be:am ,is ,are,was were 构成否定式时，一律在后面加否定词 not He is reading. →He is not reading. They are from China. →They are not from China. 2. 情态动词的否定式 情态动词：can, could, must , may, might, will, would，shall,should , need,…… 构成否定式时，一律在情态动词后面加否定词 not I can swim. →I can not swim. You should arrive here on time. →You should not arrive here on time. 3. 实意动词的否定句 实意动词：即行为动词, 表示动作的动词。它分为及物动词和不及物动词两种（及物动词是指后面要求有宾语的动词；不及物动词指后面不需要跟宾语的动词） 构成否定式时，要借助助动词 do, does, did，在一般现在时中用do 或者 does，在一般过去时中用did。 结构为：主语+don’t\doesn’t\didn’t+动词原形+其它 I like pop music. →I don’t like pop music. She often swims. →She doesn’t often swim. He handed in his homework. →He didn’t hand in his homework. 一般疑问句 含义：一般疑问句是疑问句的一种。它是只用yes（是）或 no（否）来回答的句子。其结构是：系动词 be/助动词/情态动词+主语+其他成分 1) 谓语 动词是 be 动词 规律： He is a student. Is he a student? 2 She is swimming. Is she swimming? 2) 谓语中含有助动词have/has/had (通常是在现在完成时和过去完成时中：have / has / had + 过去分词) 规律： Tom has finished his homework. →Has Tom finished his homework? I have eaten breakfast. →Have you eaten breakfast? 3) 谓语动词中含有情态动词时。 规律： He can swim. →Can he swim? I should go to school. →Should I go to school? 4) 谓语动词是行为动词，必须在句首加上助动词。加上这些助动词后，句子中谓语动词必须用原形。 规律： Tom built a science lab himself lab...
