It is mainly because of my fault.

这主要是由于我的过错。

《新英汉大辞典》

Although some of this can be attributed to a higher income, Manton believes it is mainly because educated people seek more medical attention.

虽然部分原因可以归结为较高的收入，但曼顿认为这主要是因为受过教育的人会寻求更多治疗。

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It is mainly because that the position of the branded apparel is not high enough yet.

困扰服装品牌地位提高的主要因素是缺乏对品牌服装理念的系统研究。

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But if money remains cheap, it is mainly because of worries about deflation.

ECONOMIST: American banks

But it is mainly because many middle-sized companies were clients of both banks.

ECONOMIST: Germany's looming credit crunch

There is some suspense here, even if it is mainly because the violence when it comes is so swift and sickening.

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