A policeman___the thief and catch him (knocked at/knocked ou

He knocked ___an old man and knocked him ___ .A.into,into B. They knocked him down and ( )him of this bag.A.rob B.robbed the ball ___ him very hard a.knocked at b.beat c.bounced d.h knoced at 和knocked The man knocked him dowm and ___him of this bag. One evening,three old men came to a house and knocked at the He knocked him down with a sharp blow.He ___ ____ night,a stranger knocked at the door. knocked at my door 和 knocked my door 区别? knocked at和knocked on有什么区别? 是knocked at the door还是knocked on the door -----------,a car knocked her down.