含有實義動詞句，Do和Does來出力；單三主語用Does，其余人稱都用Do；一般疑問很好變，Do和Does提句前；句首是Do是Does，后面動詞都還原；否定句也不難，主語后don’t，doesn’t跟上前；不論疑問否定句，人稱或是一二三，實義動詞必還原，does、has永不見。

1.肯定句

(1)I have a blue book.

(2)He has a brother.

(3)She wants to be a teacher.

(4)They like to play basketball.

2.否定句：主語+don’t/doesn’t+動詞原形。其中do/does為助動詞，是來幫助實義動詞構(gòu)成否定或疑問句的，但加了do/does后，其后面的動詞必須用動詞原形。

(1)I have a blue book.(變?yōu)榉穸ň?→I don’t have a blue book.

(2)He has a brother.(變?yōu)榉穸ň?→He doesn’t have brother.

(3)She wants to be a teacher.(變?yōu)榉穸ň?→She doesn’t want to be a teacher.

(4)They like to play basketball.(變?yōu)榉穸ň?→They don’t like to play basketball.

3.一般疑問句：Do/Does +主語+動詞原形+其他？句中加了do/does后，其后面的動詞還是必須用動詞原形。

(1)I have a blue book.(變?yōu)橐话阋蓡柧?→Do you have a blue book?

(2)He has a brother.(變?yōu)橐话阋蓡柧?→Does he have a brother?

(3)My brother does his homework before supper.(變?yōu)橐话阋蓡柧?→Does your brother do his homework before supper?

(4)She wants to be a teacher.(變?yōu)橐话阋蓡柧?→Does she want to be a teacher?

(5)They like to play basketball.(變?yōu)橐话阋蓡柧?→Do they like to play basketball?

4.特殊疑問句：特殊疑問詞+一般疑問句?

(1)Your sister likes English best because it’s interesting.(對加粗部分提問)→Why does your sister like English best?

(2)He does his homework before supper.(對加粗部分提問)→When does he do his homework?

注意：當含有and引導(dǎo)的短語在句中做謂語或賓語，我們把這類句子變否定句時，必須把and變?yōu)閛r.如：

(1)He can swim and dance.(變?yōu)榉穸ň?→He can’t swim or dance.

(2)My father likes English and math.(變?yōu)榉穸ň?→My father doesn’t like English or math.

5.but和except后。but前是實義動詞do時，后面出現(xiàn)的不定式不帶to。

例如：He wants to do nothing but go out.他只想出去玩。

比較：He wants to believe anything but to take the medicine.除了吃這藥，他什么都信。