In particularly wet years, short stretches of an otherwise dry stream-bed may have flowing water because the water table rises to intersect the land surface.

在气候特别湿润的年月里，平常干涸的河床下游可能会有水流动，因为地下水在那里位抬升到了地表以上。

youdao

The water had raced down the slope and scoured out the bed of a stream.

水顺着山坡流下来，冲刷出一条小河道。

《牛津词典》

The prospector panned off bits of sand and gravel scooped from the bed of a stream.

探矿者淘选从河床中挖出的少量含金泥砂和沙砾。

youdao

There was no trail that the young man could see, but they were working up and around the face of the mountain and now they crossed a small stream and the old man went steadily on ahead up the edge of the rocky stream bed.

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He sat now by the stream watching the clear water flowing between the rocks and, across the stream, he noticed there was a thick bed of watercress.

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In the centre of Tafraoute, sheep make their way up a dry stream bed.

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