Question

【题目】Tomorrow we’ll have a school trip. But Sally _______ (has to/ had to) stay at home to look after her sick mother.

Answer 1

【答案】has to

【解析】

句意：明天我们将会有一个学校旅行，但是Sally必须待在家照顾他生病的妈妈。Sally是单三人称，动词应该用单三动词has to。故答案为has to。