Give me one good reason why I should help you.

我为什么要帮你？给我一个充分的理由。

《牛津词典》

There is no earthly reason why they should ever change.

他们毫无理由改变。

《柯林斯英汉双解大词典》

That was the very reason why he felt a certain bitterness.

那正是他感到有点痛苦的原因。

《柯林斯英汉双解大词典》

Some Americans had trouble understanding the economic reason why food had to be destroyed so people could have enough to eat.

VOA: special.2011.03.24

The reason why literacy is required of everyone is because we don't live to 200.

为何每个人都需要文化素养？,因为我们活不到200岁,我们出于对外界的好奇。

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I think the reason why triathlon is not so, so big is just because it requires a lot of time.

我认为铁人三项运动之所以不够普及，
是因为它需要大量的时间。

对体育项目的热爱 - SpeakingMax英语口语达人

Critics see a different reason why products like eggs and hamburger rise to the top.

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The reason why I'm massively excited this morning is because it is transfer deadline day.

BBC: Transfer deadline day as it happened

That may be one reason why the SEC settled with him first, LeBeau says.

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