Cars are mostly metal.

汽车大多是金属制成的。

《柯林斯英汉双解大词典》

It's mostly metal, but there's a little wooden handle, too.

大部分是金属，但是有一个小巧的木制把手。

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Chondrules and inclusions in Allende are held together by the chondrite matrix, a mixture of fine-grained, mostly silicate minerals that also includes grains of iron metal and iron sulfide.

阿伦德陨星里的陨石球粒和内含物是由球粒陨石基质结合到一起的；这是一种细粒混合物，主要包括铁颗粒和硫化铁的硅酸盐矿物。

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Their weightless-looking structures were mostly made of glass and metal.

VOA: special.2009.12.13

There's an important distinction between these two types of objects: Comets are mostly water, ice and dust, while asteroids are mostly rock or metal.

CNN: While you were working: An asteroid just flew by

In the nineties, a range of American acts began drawing from the work of Norwegian metal bands that were famous mostly for a look and for several unpleasant events.

NEWYORKER: The Dark Arts

Investors should expect depressed results, mostly impacted by lower iron ore prices and a lack of contribution from its base metal division, which should remain in the red.

FORBES: For Brazil's Vale, A Case Of Lowered Expectations