Unit 4Dont eat in class. Section A(Grammar Focus3c,考点 have to 必须;不得不 *We have to be quiet in the library. 我们在图书馆里必须保持安静。(教材P21) *Peter has to wear a uniform at school. 彼得在学校里必须穿校服,They dont have to come to school every day. 他们不必每天来学校,自主归纳】 have to意为“必须;不得不”, 后接动词的原形, 有人称和时态的变化, 其第三人称单数形式是has to, 过去式形式是had to, 疑问形式和否定形式需要借助于助动词do/does, did,妙辨异同】have to与must的区别,即学活用】 戴夫家离学校很远, 他每天早晨必须早早起床。 Daves home is far from school. He _ _ _up early every morning. They have to be quiet in the dining hall.
