I was about to go out when there was a knock at the door
敲门───knock at the door;正要───just
They were interrupted by a knock at the door.───他们被敲门声打断了。
a knock at the door.───门外传来敲门声。
I was wakened by a knock at the door.───敲门声把我吵醒了。
I was just about to fall asleep when there was a knock at the door.───我刚要睡觉，有人就敲上门了。
But now, before I come to knock at the door of adulthood I feel anxious to express my own opinions on this saying.───但是现在，在我即将跨如成年人行列时，我急切地想要把我对这句话的看法表达出来。
One evening, little Hans was sitting near the fire when he heard a loud knock at the door.───一天晚上，小汉斯正坐在火炉旁，突然听到有人使劲敲门。
Did I hear a knock at the door?
There was a treble knock at the door.
They were interrupted by a knock at the door.
I was wakened by a knock at the door.
A loud knock at the door made her start.