We must cut down on the amount of material we use.

我们必须削减原料使用量。

《新英汉大辞典》

The mounting labor and material costs of good times cut down his margin until it disappears and he abandons his mine.

在经济繁荣时期，劳动力和材料成本不断上升，金矿的利润缩水，直至无利可图，此时，矿主会放弃开采。

youdao

If you cut down on meat, you will be 'saving food', since raising livestock costs more plant material than the energy and nutrition you would get from eating the plants themselves.

假如你减少肉食，你将，因为养育活体所耗的植物物质的能量和营养要比你直接从食用植物本身多很多。

youdao

With steel manufacturers already under pressure due to increased raw material prices, it was inevitable that they cut down on production to combat the decline in the steel prices.

FORBES: ArcelorMitttal Cuts Production As Steel Demand Falls