The Yak-3 airframe was created as light as possible to save weight and gain more speed and manoeuvrability.

为了增加速度和机动性，雅克3的机身被设计得尽可能轻巧。

youdao

It also increases the use of costly carbon-fiber body panels (the hood and roof) and other composite materials, to save weight.

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This is what happens to the supplements that were pulled out, to save weight, by that newsagents on virtuous Mersea Island.

BBC

Built of plastic to save weight, it was more akin to a scooter than to a bicycle, and it ran on a pair of lead-acid batteries, similar to those under the hood of a car.

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