This is a commonly used fixed expression.

这是一种常用的固定表达。

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A slender forty-nine-year-old with salt-and-pepper hair and a fixed expression, he wore a dark suit with a collarless striped shirt.

马沙49岁，身材修长，头发斑白，脸上的表情一成不变。他穿一套深色西装，里面是一件无领子的条纹T恤。

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Idiom is a unique fixed expression of a language in the course of using. Both English and Chinese idioms are very rich, reflecting the different cultural characteristics of the two peoples.

习语是某一语言在使用过程中形成的独特的固定的表达方式，英汉两种语言都有极为丰富的习语，反映了两个民族不同的文化特点。

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Nor can I buy the argument, made here by Joe Weisenthal, that the abandonment of gold equates to a new expression of faith by investors that central bankers and policy makers have more or less fixed our economic problems and that its better to be in stocks, not rocks.

FORBES: Gold Inches Up As Goldbugs Seek Reasons For Historic Rout