On his way home,he heard a voice _____(call) him.请问各位大大,中间应填什么形式,为什么呢

问题描述:

On his way home,he heard a voice _____(call) him.请问各位大大,中间应填什么形式,为什么呢

ing形式hear,see,notice,watch后加ing形式动词表示看见正在做某事,加do表示经常在做某事