The substance polymerizes to form a hard plastic.

这种物质聚合形成坚硬的塑料。

《牛津词典》

Too big a socket, and those hard plastic discs, ungripped, simply fall out.

耳朵孔太大，那些硬硬的塑料耳塞很容易掉出来。

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They are usually tall wooden walls with hard plastic handholds set at various angles.

通常是高大的木墙，设置不同角度的硬质塑料岩点。

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Throw away damaged metal cans or hard plastic containers.

VOA: special.2010.07.19

The interior gets softer materials instead of hard plastic as well as silver, satin and chrome-plated accents.

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Shoes made of hard plastic may improve matters, especially as they can be glued rather than nailed on to hooves.

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Each holding a calculator in their hand, the customer types in a number, each strong keystroke resonating against the hard plastic.

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