题目内容：

把I can swim改成否定名,一般疑问句,否定回答和肯定回答.情态动词在过去式中怎么用

优质解答

否定 I can't swim
一般疑问：Can you swim?
肯定回答:Yes,I can.
否定回答：No,I can't.
can的过去式是could

追问：

把 I could swim.改成否定名，一般疑问句，否定回答和肯定回答

追答：

I couldn't swim 否定句 Could you swim? 一般疑问句 Yes, I could. 肯定回答 No, I couldn't.否定回答