1.We were at the stationer's on Monday.变一般疑问句
Were you at the stationer's on Monday?
2.There were many students in this school last year.改为否定句
There( were ) ( not )many students in this school last year.
3.Peter often helps his mother in the house at the weekend.改为一般疑问句
（ Does ）Peter often( help )his mother in the house at the weekend?