students mustn't----(stand)on the chair in the classroom,适当地动词适当地动词
问题描述:
students mustn't----(stand)on the chair in the classroom,适当地动词适当地动词
答
stand,不用其他时态
students mustn't----(stand)on the chair in the classroom,适当地动词适当地动词
stand,不用其他时态