knock at

• Fortune knocks at least once at every man ' s gate
  好运至少在每个人的门上敲一次。
• She ' d let a wolf in if it knocked at the door ,
  就算一匹狼敲她家门她也会放它进去
• Somebody s knocking at the door . i ll answer it
  有人在敲门，我还是要学它。
• The doctor ' s daughter knocked at the locked door
  医生的女儿敲了上了锁的门。
• What were you doing when i knocked at the door
  （我敲门的时候你在干什么？ ）
• Pinkerton and the consul knock at the door and enter
  平克顿和领事敲门进来。
• I knocked at the office door many times just now
  我刚才敲了多次办公室的门。
• She faltered before knocking at his door
  在敲他的门之前，她犹豫不决起来了。
• I was cooking when she knocked at the door
  我正在做饭，突然听到她的敲门声。
• While he was sleeping , someone knocked at the door
  正在他睡觉时，有人敲门。