I heard him knock three times.我听见他敲了三次,这个knock为什么不用过去式?

I heard him knock three times.我听见他敲了三次,这个knock为什么不用过去式? While i was reading i heard someone____at the door of partiesA knocked B knocks C to knock D knock I've never heard of him before. When I was doing my homework ,I heard someone (knock) at the door. 改错:I was just (falling sleep) last night (when) I (heard) a knock (at) the door. I heard him singing改为被动语态which is correct?then I heard him sing? Just at that time,I heard someone____at the doorA.knockB.knocksC.knockedD.to knock I heard someone _____(knock /knocking) at the door just now .横线上应填什么?为什么 I heard him singing there改被动句是heard singing还是heard to sing i was watching tv when i heard the door(knocking)i was watching tv when i heard someone(knocked)at the door两个knock形式对吗? .When I passed by his door,I heard him _____________. After a knock at the door,the child heard his mother's voice him.A.callingB.calledc.being calledd.to call选项是在VOICE和HIM之间 I heard from him last week的意思 i know you're afraid of heard from him,是什么意思? last night i heard him driving his pigs to market. What did you hear last night? I seemed someone knock at the door.A hearB.to have heardC.to hearD.having heard [-A75] After a knock at the door,the child heard his mother's voice ______ him.A.calling B.called C.being called D.to call The villagers had many trees ___ ( plant ) just then .They managed to make themselves ___ ( understand ) in very simple Eng .I heard the song _____（sing） in English .I heard her ___ (sing) the song in Eng.I saw him ___( open )the window .I saw th