加动词原形和动词ing形式都可以.hear + 原形 表示 听见了已经完成的动作hear + ing 表示 听见了这个动作正在进行
1、听到，听见，hear sth.+vt.及物动词。如：I heard a strange voice just now.
2、hear of听说。如：I heard of him before.
hear from 收到某人来信。如：I am glad to hear from you.
3。hear sb do sth 听到某人做某事 。如:I heard Tom sing yesterday.
4、hear sb doing sth 听到某人正在做某事如：I heard Tom singing in the classroom when I came in yesterday.
5、hear +that 从句。如：I heard that Liu Dong had passed the exam
