I hear him ___ (sing) this English song at ten o'clock yesterday morning.用doing形式还是do的形式?
问题描述：
I hear him ___ (sing) this English song at ten o'clock yesterday morning.用doing形式还是do的形式?
答
I hear him ___ (sing) this English song at ten o'clock yesterday morning.用doing形式还是do的形式?回答：singing根据后面的时间状语“at ten o'clock yesterday morning”,这里用ing形式....