有时她发音不清楚。

Sometimes she can't pronounce the words clearly.

youdao

但重要的问题还是，他说，比如，雄性驼背鲸有时候在进入或离开一个竞争性群体时唱歌，但研究者不清楚唱歌在其中起什么作用。

But important questions remain, he says. For example, male humpback whales sometimes sing as they move in and out of competitive groups, but researchers don't know what role the songs play in mating.

youdao

他参与的确切性质还不清楚，但是在以往的调查中，警方有时会逮捕这些没有在网络上隐藏踪迹的小人物。

The precise nature of his involvement was unclear, but in past investigations, the authorities have sometimes arrested those unsophisticated enough not to cover their tracks on the Web.

youdao