初中英语特殊疑问句完成句子

They didn't arrive on time because they got up late．（对划线部分提问）     

　　they arrive on time？

Dave was making a model plane in the classroom at that time．（对划线部分提问）

　　 Dave making a model plane at that time？

Lee has helped the local people sell their products __________________．（对划线部分提问）

　　　　has Lee helped the local people sell their products？