"There's a party tonight."—"Is that why you're phoning?"

“今晚有聚会。”—“那就是你打电话的原因吗？”

《柯林斯英汉双解大词典》

Isn't that why we moved here?

这难道不是我们搬来这里的原因吗？

youdao

Is that why you don't to go home?

就是这个缘故，你才不想回家的吗？

youdao

"That's why we need strong rules of the road to guard against the kind of systemic risks we have seen.

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So be honest now: was that why most of you chose easy?

坦白地讲,这是你们的理由吗

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And that's not very English and I think that's why he is a bit more shocking, not on English television,

那不是很有英国范儿，我想这就是为什么他有一些骇人的，不是在英国电视上，

认识戈登•拉姆齐吗？ - SpeakingMax英语口语达人

Is that why the company is rumored to be getting into the phone business?

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Isn't that why union members strike rather than accept forced overtime at 150% of straight pay?

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Is that why it could be at least considered a criminal violation to destroy them?

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