He cannot be 100% sure because the transfer needs more time to be sorted out.

之所以不说100%，是因为转会还需要时间。

youdao

“We cannot yet be sure that there is an irreversible change in the trend, ” he told a parliamentary debate on joblessness on November18th.

“我们尚不能确定不可逆变化会存在于这种趋势中，”他说在11月18日这天，国会还就失业问题进行了辩论。

youdao

He almost certainly attended the Grammar School in the town, but of this we cannot be sure.

几乎可以肯定，他是在镇上念的文法学校，但对此我们没有绝对把握。

youdao

But he says he cannot be sure why Mariam Khatib died until the samples are analysed.

BBC: Middle East

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

ECONOMIST: Lords reform

Some will say he didn't mention them because he cannot be sure of achieving either growth or deficit reduction in 2012.

BBC: George Osborne chooses his words carefully