A2
S + must + V0 · S + have to / has to + V0 · S + had to + V0
must, have to 和 had to
讲解
must 没有过去式，所以说过去的必须只能用 had to。要记住三个不同的层次：mustn't 是禁止，don't have to 是不必，didn't have to 是当时不必。 常见陷阱：must 的过去式【不是】musted：I musted go ✗, I had to go ✓。
例句
I had to work last Saturday.
上周六我得去上班。
You must not touch that.
你不能碰那个。
We do not have to pay.
我们不用付钱。
She did not have to come.
她当时不必来。
练习
通过选择题测试你的掌握程度
高效学习“S + must + V0 · S + have to / has to + V0 · S + had to + V0”
语法点“S + must + V0 · S + have to / has to + V0 · S + had to + V0”（must, have to 和 had to）是 CEFR 2 级别的重要结构之一。要熟练运用这个结构，你需要弄清楚它的使用语境，并经常练习。
学习小贴士：把例句大声朗读多遍，培养自然的语感反应。然后试着结合自己的生活情境造句。用发音按钮听标准发音并跟着练习。
你也可以查看完整课程“”，更深入地了解相关的语法和词汇。