I've heard rumours, but nothing definite.

我听到一些流言，但都不确定。

《牛津词典》

I have looked at a lot of examples on here, but nothing seems very definite to me.

我已经看了很多的例子在这里，但似乎没有很明确的。

youdao

Once leather Ka is case Ceng Yuteng with be suspected of forestall and unfair competition dispatch litigates, but final result also is to end up with nothing definite.

曾经皮咔以涉嫌垄断和不正当竞争为案曾与腾讯对簿公堂，但最后的结果也是不了了之。

youdao

"I had a vague idea that there was a connection but nothing definite, " he said.

BBC: London man 'amazed' to learn of Abraham Lincoln connection

He has said previously he would think about running in 2016, but nothing is a definite yet.

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