As the grinding goes on, the pieces get small. Over a long time, tiny grains of sand are made.

在风浪的冲刷下，这些碎粒被磨得越来越小，很久以后就形成了很小的沙粒。

youdao

Women once spent long hours grinding grain by hand.

妇女曾经在手工研磨谷物上花上大半天的时间。

youdao

Grinding of ultra sharp, high hardness, wear long life paper round.

打磨部采用超锋利、高硬度、超长寿命磨纸轮。

youdao

The stickiness of house prices suggests the drag on consumer spending will be long and grinding, not sudden and sharp.

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Indeed, of the 109 players who appeared in the final of the World Cup or the Euros since 2004, just 15 did so after a long and grinding Premier League season.

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The coastal road to Sablayan was notoriously bad, requiring a long, grinding bus journey from the nearest ports -- Abra de Ilog to the north, or the provincial capital, San Jose, to the south.

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