We can use either the infinitive without to or the -ing form after the object of verbs such as hear, see, notice, watch. The …
1.主动语态中,hear只能接不带to的不定式或动名词作宾语即： hear sb do sth:I heard her sing that song.我听见过她唱那首歌. hear …
(1) hear sb do sth 听见某人已经做了某事情(强调听见整个过程，属于一种回忆性描述） (2)hear sb doing sth 听见某人正在做某事 …
更多内容请点击：Hear, see, etc. + object + infinitive or - ing - Cambridge Grammar