be动词-情态动词及助动词用法

1、七年级英语双休日作业班级：姓名：等级英语句型变化总结练习1、含有be动词am , is , are 构成的句子：变一般疑问句时把am , is , are提到句子的前面，句尾用问号即可。变否定句时直接在am , is , are后面加not即可。例如：肯定句：He is a student.一般疑问句：a student?否定句:He a student.肯定句： We are from China.一般疑问句：from China?否定句：We from China2 .由情态动词can, may, should等构成的句子：变一般疑问句时把can, may,提到句子的前面，句尾用问号即可.

2、变否定句时直接在can, may,后面加not即可.例如：肯定句：She can swim.一般疑问句： she swim?否定句:She swim.3 .由行为动词构成的句子：需要加助词do或does.变一般疑问句时把do/does放在句子前面.变否定句时在主语后面加don 't / doesn't ,谓语用动词原形。例如：肯定句:They play football after school.一般疑问句：play football after school?否定旬：They football after school.肯定何： Tom watches TV every da

3、y.一般疑问旬： Tom TV every day?否定旬：Tom TV every day.注意：变否定句时相关词的改变肯定句变否定句时，除将谓语变为否定式外，句中其他词语也可 能随之改变：如将 some 改为 any , too 和 also 改为 either , and 改为 or等: There are some birds in the tree.树上有些鸟。There aren't birds in the tree.树上没有鸟。He likes the book, too.他也喜欢这本书。 He doesn' t like the book, .他也不喜欢这本书

4、。He likes singing and dancing.他喜欢唱歌和跳舞。 He doesn' t like singing dancing.他不喜欢唱歌也不喜欢跳舞。补充练习：根据句后括号内的要求，填入句中所缺的词：1. I know the answer.（一般疑问句）know the answer?2. We can see some birds.（一般疑问句）see birds?3. There is a computer in the house.（一般疑问句 ）a computer in the house?4. There are some flowers on th

5、e teachersdesk.（ 一般疑问句 ）any flowers on the teachersdesk?5. There are some apples on the tree.（否定式）There apples on the tree.6. I think he is old.（否定句） I think he old.7. Open the window.（否定句） open the window.8. We can speak good English.（变否定句）We speak good English.9. Thank you for helping me.（同义句）Than

6、k you for.10. Whose is this book?（同义句）is this?11. This is her book.（同义句） This book.12. Her sweater is red. （ 对划线部分提问）is her sweater?13. My pencils are in the pencil-box.（ 对划线部分提问）your pencils?14. I get up at six every day.（对划线部分提问）do you get up every day?15. There are fifty students in my class.（对划线部分提问）students are there in your class?16. These are cars.（ 用buses 改写成选择疑问句） Are these cars?17. The book is in my schoolbag.（变疑问句）the book in your school-bag?18. Two boys are in our house.（改为 there be句型）