我试着敲了敲后门，但没人回答。
如果前门锁着，就敲后门试试。
如果前门没有人听到，你就试试敲后门。
Try knocking at the back door if nobody hears you at the front door.
如果前门没有听见你敲门，就试试去敲后门吧。
Try knocking AT the back if nobody hears you AT the front door.
如果前门没人听见你敲门，可以敲后门试一下。
如果前门没有人听见你敲门，为什么不试试敲后门呢？
Why not try knocking at the back door if nobody hears you at the front door?
小狗成为我们家一员约两年后，一天，有个流浪汉敲我们家后门，问我们能否给他点吃的。
The little dog had been a part of our family for about two years when a hobo knocked at the back door and asked if we could give him something to eat.
有一次，我听见敲桌子的声音，之后门“吱呀”开了一小条缝隙，然后我有听见了一些敲击声。
Once, I heard knocks on my table, then the door creek and open a little, then following by several knock around me.
有一次，我听见敲桌子的声音，之后门“吱呀”开了一小条缝隙，然后我有听见了一些敲击声。
Once, I heard knocks on my table, then the door creek and open a little, then following by several knock around me.
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