Without a doubt, it's the most important step towards being a happy person.

不要怀疑，这是迈向快乐的重要基石。

youdao

Even if it changed drastically for the better, If you weren’t happy in the first place, I very much doubt that you’ll be happy after the change.

即使为了快乐大幅度的转变，如果你一开始就不开心，我很不确定改变之后的你是否会感到快乐。

youdao

The second question may be unasked, but don’t doubt that it is in your child’s mind: “If you can stop being happy together, can you stop being happy with me?”

孩子的第二个问题未必会问出口，可是不要怀疑这个问题的存在：“如果你们生活在一起不能感到快乐，那跟我在一起会不会也一样呢？”

youdao

"I doubt if you can understand how happy this modernizing has made me.

VOA: special.2009.12.07

Carriers, no doubt, would be happy to have a third strong alternative to Apple and Android phones.

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Nine in ten of the original employees still have jobs, says the company, no doubt making the government happy.

ECONOMIST: German restructuring

All this has commodities traders quite busy--and happy, no doubt.

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