Tom had a good time last weekend.
否定句 ：Tom didn't have a good time last weekend.
疑问句 : Did Tom have a good time last weekend ?
肯定回答： Yes , he did .
否定回答： No ,he didn't .
We often played computer games last year.
否定句 ：We didn't often play computer games last year.
疑问句 : Did you often play computer games last year ?
肯定回答： Yes , we did .
否定回答： No ,we didn't .