My new car is economical of fuel.

我的新汽车节省燃料[不费油]。

youdao

My new car is economical of fuel.

我的新汽车节省燃料[ 不费油]。

youdao

The man is economical of his time.

这人很节约时间。

youdao

Well, I think possibly they see a nuclear weapons as a more economical way of defending themselves.

NPR: North Korea Test Aimed at Internal Audience?

While the law did not name MTBE, the chemical was a more economical means of oxygenating gasoline than the obvious alternative, ethanol.

FORBES: Demonizing for Dollars

Solar thermal power, which is the most economical form of solar power production, additionally consumes at least double the water of conventional power plants.

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