历史学习需要时空想象力。“1991年的欧洲”会让你想到的词语是( )
农民拔除稻田中的稗草;清除鱼糖中食肉的“黑鱼”,这种做法是为了()
—I think students should have mobile phones to call their parents.
—________. They often use them to play games instead.