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1·Wild ducks jet up and down the blue waters in spring and autumn, and fly fishermen wade the riffles, casting leisurely.

在春天和秋天，野鸭在湛蓝的水中飞上飞下，飞钓者涉过急流，悠闲地抛出鱼钩。

2·While Google could previously be used to look for specific strings, now the search engine riffles through code that much better.

在过去，Google可以被用于寻找特定字符串；而现在搜索引擎已经可以更有效地搜寻代码。

3·Riffles placed transversely along the bottom of the sluice cause the water to eddy into small basins, retarding the current so that gold may settle.

横置于水闸底部的格条使得水流旋转进入小水池，使水流减速，沈淀出黄金。