use
It's no use
用：后接动名词短语，表示不赞成做某种努力·
意：...没用;…没希望;…不可能
例，It's no use complaining to him about this; he's not the powers that be.
这事向他抱怨没用，他不是当官的。
It's no use, we'll newer find our way out of this bloody mess!
没希望了，这该死的烂摊子我们是理不清了!
used
（be）used to...
用：也说get used to...，后接动名词短语，是用来表示习惯于做某事的句子结构。
意：习惯…;适应..
例： I'm quite used to working with him now.
现在我已很习惯跟他在一起工作了。
You'll soon get used to (eating) French food.
很快你就会吃惯法国餐的。
Are you used to drinking in a bar?
你习惯在酒吧里喝酒吗?
