What was going through the killer's mind is a matter for conjecture.

凶手作案时心里是怎样想的，这个问题只能由人们去推测了。

《牛津词典》

She was thinking over what she had heard about Heidi, making up her mind to look into the matter.

她正在仔细考虑着她所听到的关于海蒂的事情，决定调查一下这件事。

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If you wait until the matter disappears from the person's mind, they might not understand what you're trying to tell them.

如果你等到这件事从对方的脑海中消失，他们可能不明白你想告诉他们的事情。

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Its sole purpose is to prepare the mind and body to overcome any obstacle no matter what the circumstance.

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No matter what we're shopping for, we can now select from a mind-boggling array of high-quality, reasonably priced merchandise.

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