He shrank back against the wall as he heard them approaching.

听见他们朝这边来，他退到墙根。

《牛津词典》

Put your back against the wall.

把背靠在墙上。

youdao

Respiratory took over the CPR and I stood back against the wall, bloody and disbelieving.

呼吸科医师接过心脏起搏器，我背靠墙站着，到处都血淋淋的，令人不敢相信。

youdao

I quickly stood up. My back was against the cave wall.

VOA: special.2010.07.10

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