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 ;hear sb doing 在被动语态中,要将不定式前加上to,即:be heard to do;be heard doing
你所提是在被动语态中,所以be heard to doing不存在。 be heard to do 被听说将去做某 be heard to be doing 是to do 的进行时:被听说正在做某事 be heard doing 被听说(近期)一直在做某事
另,不定式一般时、进行时和完成时的区别 He is believed to come.(=It is believed that he will come.) 要来,还没来 He is believed to be coming.(=It is believed that he is coming.) 正在来路上 He is believed to have come.(= It is believed that he has come.) 已经来了
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 sb doing sth :I heard her singing that song. 我听见她在唱那首歌。 2.但是,在被动语态中,又要将不定式前加上to,就以上面两句为例: She was heard to sing that song. 她被人听到过唱那首歌。 She was heard singing that song。 她正在唱那首歌时被人听到了。追问