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- I wonder who could be knocking at the door so late? 我奇怪都这么晚了，是谁在敲门?
- Whoever can that be knocking at the door? 敲门的会是谁呢?
- Someone was knocking at the door. 有人在敲门。
- For many centuries, nonphysical mathematics had been knocking at the door waiting to be let in. 非实体数学敲门等入已经有几个世纪了。
- I seem to hear someone knocking at the door. 我好像听到有人在敲门。
- Someone is knocking at the door. 有人在敲门。
- There was a furious knock at the door. 有人在猛烈地敲门。
- There seems to be a knock at the door. 似乎有人在敲门。
- She accidently heard someone knocking at the door. 她忽然听到有人敲门。
- He entered without knocking at the door. 他没敲门就进来了。
- It may be our teacher knocking at the door. 也许是老师在敲门。
- Did you hear the knocks at the door? 你听到敲门声了吗？
- There came a knocking at the door. 传来一声敲门声。
- Who's knocking at the door, do you know? 你知道谁在敲门吗?
- Did you hear someone knocking at the door? 你听见有人在敲门了吗?
- He was awakened by someone's knocking at the door. 他被某人的敲门声吵醒了。
- There is someone knocking at the door. 有人敲门。
- It sounds as if someone is knocking at the door. 听起来好像有人在敲门。
- I knocked at the door but no one answered. 我敲了门,但无人应答。
- Do you hear someone knocking at the door? 有人敲门你听见了吗?
