我一开始就知道那是不合算的。

I knew right from the beginning that it would not pay.

youdao

如果买一大袋水果最后让它们在冰箱里烂掉就不合算了。

It's not economical to buy a big bag of fruit if it's going to end up rotting in the refrigerator.

youdao

像太阳一样产生能量可能会太便宜以至于无法计费，或是像永动机一样太不合算。

Making energy like the sun does might too cheap to meter or as uneconomical as a perpetual motion machine.

youdao

Oftentimes, inventions that seem, in the abstract, to be good ideas may be impossible because something that you have to do to make it actually come into practice is too expensive and so it's not economic to produce the invention.

通常在理论上,创新固然不错,但却很难实现,因为把创意变成现实,花费会相当的昂贵,实现这样的创意非常不合算

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