Their firm have contracted to build a double-purpose bridge across the river.
他们公司已签约承建一座横跨大江的两用大桥。
Education has a double purpose, it is a combination involving teaching and educating people.
教育的目的是双重的，是教书与育人的统一体。
This machine serves a double purpose.
这部机器有双重用途。
They hoped that it would serve a double purpose.
他们希望这能起双重作用。
这有双重的目的、作用。
这有双重的目的、作用。
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