knocked at和knocked on有什么区别?

knoced at 和knocked knocked at knocked at和knocked on有什么区别? Knocked knocked at my door 和 knocked my door 区别?knocked at my door 和 knocked my door 区别? 是knocked at the door还是knocked on the door knocked是什么意思 knocked-up My cat___a cup of water and ran away.A.knock at B.knocked over C.knocked out D.knocked on knock 短语The little boy run for the football and ___a man standing there.A.knocked down B.knocked at C.knocked into D.knocked He__a glass of milk just now.He was very careless.a.knocked.b.knocked on.c.knocked over.d.knocked oHe__a glass of milk just now.He was very careless.a.knocked at.b.knocked on.c.knocked over.d.knocked off She went d_____to see who knocked at the door. the man knocked l_ at the door now. 18. He knocked at the door _________ no one answered. I () my brother when someone knocked at the doorI () (telephone)my brother when someone knocked at the door 英语knocked.started.英语knocked.started. He knocked ___an old man and knocked him ___ .A.into,into B.into,down C.down,on D.at onHe knocked ___an old man and knocked him ___ .A.into,into B.into,downC.down,onD.at on I heard someone ____(knocking/knocked)at the door just now.那用knocked也满足hear加从句呀？