Local residents said, before being polluted, clear bottom.

当地居民说，在被污染之前，水清见底。

youdao

By adsorption and decomposition experiment, interaction of sewage with high COD and clear bottom sediment was studied.

通过底泥吸附和污水有机物降解实验，研究了高COD浓度污水与洁净底泥的相互作用。

youdao

The water was so clear we could see the bottom of the lake.

湖水清澈见底。

《牛津词典》

"We have now to concretize the measure which have been agreed upon 11 April and we have to send a clear signal that we will not let down Greece, and I think that is the bottom line of everything."

VOA: standard.2010.04.28

Newtown pulled clear of bottom-placed Welshpool (who lost to Wem) with a six-wicket success against Shelton.

BBC: Wellington and Whitchurch go up

The win lifts the Paisley side five points clear of bottom side Falkirk.

BBC: Manager Gus MacPherson hails four-star St Mirren

With Falkirk drawing at home to St Johnstone, Killie move two points clear of bottom-placed Bairns, who visit Rugby Park in Saturday's season finale.

BBC: Sport - Football - Aberdeen 1-2 Kilmarnock