They didn't play a balloon.
3、借助于did 将行为动词构成的一般过去时的陈述句改为一般疑问句。需注意的是改后的一般疑问句要用动词原形。
Did I
Did you visit the zoo last sunday?
Did he（she）
Did it play a balloon?
Did we
Did you visit the zoo last sunday?
Did they
Did they play a balloon?
一般过去时一般疑问句的肯定回答和否定回答。
Did I visit?
Yes, you did.
No, you didn't.
Did you visit?
Yes, I did.
No, I didn't.
Did he（she,it） play?
Yes, he（she,it） did.
No, he（she,it） didn't.
Did we visit?
Yes, we（you） did.
No, we（you） didn't.
Did you visit?
Yes, we did.
No, we didn't.
Did they play?
Yes, they did.
No, they didn't.