"So why did he get interested all of a sudden?"— "Search me."

“那么他为什么突然感兴趣了呢？”—“我哪知道。”

《柯林斯英汉双解大词典》

So why hasn't it disappeared?

所以它为什么没有消失呢？

youdao

So why is he hiding?

那他为什么要藏起来呢？

youdao

"nine months." So why do they think cupcakes are so popular?

VOA: special.2010.04.12

So why don't you tell me what the formal charge should be on the sulfur atom of thionyl chloride?

那么请大家来告诉我亚硫酰氯中,的硫原子应该有多少形式电荷？

麻省理工公开课 - 化学原理课程节选

All right. It's 12:05, so why don't you go ahead and take 10 more seconds on the clicker question today.

好，现在已经，12：05，了，请大家,花十秒钟的时间做一下今天的选择题吧。

麻省理工公开课 - 化学原理课程节选

So why does Guccione, the founder of SPIN and Gear, plan to reenter publishing this year?

FORBES: Another Spin For Guccione

So why do we persist with the male mid-life crisis, talk about it, believe in it?

BBC: Viewpoint: Just what is middle age?

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

FORBES: Fact & Comment