I found it a bit strange, but I can't say why.

我发现它有点奇怪，但我说不出为什么？

youdao

I can't say why, I know that I must find a way to call out for my chance.

为何我却不知从何说起，我明白我必须找出那唯一的方法。

youdao

Drogba couldn't play. It is a problem with his foot and he was feeling a lot of pain. At the moment I can't say why.

德罗巴不能上场。他的脚部受了伤，他感觉很疼。现在我不能说原因是什么。

youdao

I've had several people say, you know, sometimes you can't ask why.

CNN: 2 would-be passengers feel relief, sadness: 'It could have been me'

Why they changed it I can't say, people just liked it better that way.

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And I understand obviously that you don't want to get into predicting future costs, but why can't you guys say how much has been spent so far over the six days, or even just last weekend?

WHITEHOUSE: Press Briefing