英語中的時態一共有八種，它們是：一般現在時、現在進行時、一般過去時、現在完成時、一般將來時、過去進行時、過去完成時、過去將來時。
今天我們所要講的就是第一種： 一般現在時——表示一般性，經常性的動作或一般性事實。
1、含有be動詞的句子
He is a teacher.
The girl is very beautiful.
Tim and Jack are students.
★變疑問句將be動詞移到句首
Is he a teacher?
Is the girl very beautiful?
Are Tim and Jack students?
★變否定句在be動詞后面加not
He is not a teacher.
The girl is not very beautiful.
Tim and Jack are not students.
★肯定回答及否定回答
Yes, he is. / No, he is not.
Yes, she is. / No, she is not.
Yes, they are. / No, they are not.
2、不含有be動詞的句子，即含有一般動詞的句子。
(1)第三人稱單數及單數名詞
He likes books.
She likes him.
The dog likes bones.
★變疑問句在句首加does, 動詞變為原型
Does he like books?
Does she like him?
Does the dog like bones?
★變否定句在主語及動詞之間加doesn't, 動詞變為原型，原句中的動詞不再有第三人稱變化。
He doesn't like books.
She doesn't like him.
The dog doesn't like bones.
★肯定回答及否定回答：
Yes, he does. / No, he doesn't.
Yes, she does. / No, she doesn't
Yes, it does. / No, it doesn't.
注意：第三人稱單數形式一般在動詞后面加S，不要和名詞復數混淆，變否定句或疑問句時名詞復數沒有任何變化。
(2)其他人稱及復數名詞
I want to have a bath.
We have some meat.
The students like smart teachers.
★變疑問句在句首加do
Do you want to have a bath?
Do we have any meat?
Do the students like smart teachers?
★變否定句在主語和動詞之間加don't.
You don't want to have a bath.
We don't have any meat.
The students don't like smart teachers.
★肯定回答及否定回答
Yes, I do. / No, I don't.
Yes, we do. / No, we don't
Yes, they do. / No, they don't.