单句改错.每句存在一处错误,请按改错格式改
1 The scientist devoted his spare time todo experime
2 The teacher told the students not be late
3 English is an useful tool
4 Why not to follw his advice?
5 What a fun it is to swim in the lake!
6 I happened to upstairs when the window was open
7 I would be grateful if you could give me some advices