“扣子”怎么读？

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这个年轻人一下子穿上衬衫，扣好了扣子。The young man slipped on the shirt and buttoned it up.外面非常冷，即使穿上大衣扣上扣子也不顶事。It was freezing out there even in his buttoned-up overcoat.他把衣领的扣子扣上，紧紧地裹住了他的粗脖子。He buttoned his collar tightly round his thic...