It is unlikely but not impossible.

这事可能性不大，但也不是不可能。

youdao

Extremely unlikely, but not impossible.

极其之小，但并非不可能。

youdao

"Unlikely but not impossible," he says.

他说：“不太可能，但并非完全不可能。”

youdao

I've had to fight our kind before. - They're not easy to kill.- EMMETT: But not impossible.

VOA: standard.other

but he's also insisting that this is an incredibly difficult, if not impossible, moment of thought.

但他同时坚持，如果可能，这对思维来说也是一个极其艰难的时刻。

耶鲁公开课 - 文学理论导论课程节选

The similes work not to sew everything up but make it impossible for us to maintain anything like the official position on a moral distinction between heavenly good and satanic evil.

这些比喻不是为了简单的拼凑，而是让我们不能,维持住任何天堂之善与撒旦之恶之间的,清晰的官方界限。

耶鲁公开课 - 弥尔顿课程节选

It will be very difficult for the Maliki government to succeed, but not impossible.

NPR: Senate Panel Studies Intelligence Community

Calling Mr Lukashenka a paranoid dictator makes dealing with him difficult, but not impossible.

ECONOMIST: A media war of words breaks out between two supposed allies

After that meeting, it is more difficult to get things right, but not impossible.

ECONOMIST: After Assad