苹果每千克m元，梨每千克n元，妈妈买了3千克苹果和1千克梨，共用去______元．
共用了（3m+n）元．
故答案为：（3m+n）．
改错。
1. Would you like having some tea? _____ ___
2. We need a egg and some bread. ____ ____
3. There are some pianoes in the room. ________
4. I don’t like to have some meat now. ______ __
5. Let’s buy some potatos and carrots. ____ ____
I ______ pictures when our English teacher came in. [ ]
A. drew
B. is drawing
C. was drawing
