You probably already watch it occasionally, so why not watch it together?

你可能已经偶尔看过，所以为什么不一起看呢？

youdao

You would have to raise everything about 30 centimeters once every 30 years, so why not make the job easier by making houses that can float.

你每30年就得把所有东西提高30厘米左右，那么为什么不建造一座可以漂浮的房子来简化这项工作呢？

youdao

Don't look too horrified, but we're about to have a great season for house spiders. So why not turn your home's arachnid invasion into a game?

不要太害怕，但是我们即将迎来家里蜘蛛的旺季。那为什么不把你家里的蜘蛛入侵变成一个游戏呢？

youdao

Everybody answered the questions well, intelligently, while he - why, dear me - he did not know anything, so to speak.

VOA: special.2009.01.03

We can't possibly know what the author meant except on the basis of our determination of the meaning of the text, so why not just focus our attention to meaning on the text?

我们无法知道作者是什么意思,除非以我们对文本意思的分析为基础，因此，为什么不仅仅将我们的注意力,集中在文本的意思上呢？

耶鲁公开课 - 文学理论导论课程节选

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

So why not also prohibit alcohol, which we disastrously tried to do 80 years ago?

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We live in a vibrant app culture, so why not make the most of it!

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So why not offer them up as the catalyst for public discussion about the PC industry?

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