一、 have to 的陳述句形式
A、 肯定式：have to + 動詞原形
1、 I have to tidy my room.我得整理房間。
2、 She has to help with the washing.她得幫忙洗衣服。
B、 否定式：don't (doesn't) + haveto + 動詞原形
1、You don't have to go if you don't want to.如果你不想去，你就不必去。
2、He doesn't have to stay at home all day. 他不必整天呆在家里。
二、have to 的一般疑問句形式及簡略答語
have to的一般疑問形式必須借助助動詞 do 或 does：
1、 Do you have to look after your sister？ 你得照看你妹妹么？
Yes, I do./ No, I don't. 是的，我得照看。/不，我不必照看。
2、 Does Jim have to do his homework? 吉姆必須做家庭作業么？
Yes, he does. / No, he doesn't. 是，他必須做。/不，他不必做。
三、have to 的特殊疑問句形式
1、 What do you have to do on Sundays?在星期天你得干什么？
2、 Why does she have to move to Paris?她為什么得遷往巴黎？
3、 Where do they have to work?他們必須在哪里工作？