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- When I fell I got a terrible knock on the head. 我摔倒时头撞得很厉害。
- Jim sat up when he heard the knock on his bedroom door. 吉姆听到敲寝室门的声音时便坐了起来。
- Knock on the door before you enter. 进屋之前要先敲门。
- I heard footsteps, then a knock on the door. 我听到脚步声，随后是敲门的声音。
- When I fall I get a terrible knock on the head. 我摔倒时头撞得很厉害。
- He got a nasty knock on the head when he fell. 他跌倒时头撞得很厉害。
- Did you hear the knock on the window? 你听见敲窗户的砰砰声了吗?
- There came the 2 P.M. knock on the door. 下午两点钟来客的敲门声响了。
- He got a nasty knock on the head. 他头部遭到重重一击。
- Then I heard a knock on my door and Usher came in. 接着我听见敲门声，鄂榭走了进来。
- There was a sharp knock on the door. 敲门声大作。
- There was a loud knock on the door just now. 刚才有一声响亮的敲门声。
- There's a knock on the door and it's Paul. 敲门声响起,是保罗。
- I'll have a test tomorrow. Knock on wood. 我明天有考试。上帝保佑!
- He accidentally knocked on (the pass from Jones). 他非故意犯规，用手向前击了(从琼斯传来的)球。
- I duly knocked on his door at three o'clock. 我准时在三点钟敲了他的门。
- He knocked on the wall and she knocked back. 他敲了敲墙壁，她在隔壁应声回敲。
- All the electrolyse process has no offspring that can hard to keep on reaction. 而采用生化法进行处理，易引起微生物活性的降低[3]，且难以对其进行有效脱色。
- Don't knock on the door, please. 请不要敲门。
- Please do not enter before knocking on the door. 进来前请先敲门。
