The workers believe it was bin Laden, but cannot be sure.

这些劳工认为那就是本·拉丹，但无法确定。

youdao

Unfortunately I favor melanin but cannot be sure from the photos.

然而，我不能从这些图片中确信是黑色素。

youdao

It maybe that some have them already, but we cannot be sure.

也许有些人已经拿到了，但我们不能肯定。

youdao

"And while we will continue to do everything we can, we cannot be sure what the future will hold, but we are doing our absolute level best."

VOA: standard.2009.07.29

In a statement, the hospital said both mother and daughter ate at the outlet in Wrexham "but cannot be sure that they picked up the infection there and are unwilling to speculate".

BBC: E.coli girl, three, 'much better'

But he cannot be sure that the commission's recommendations will conform to the government's modest wishes.

ECONOMIST: Lords reform

But you cannot be sure what will happen in the next 48 days.

CENTERFORSECURITYPOLICY: Center For Security Policy