It doesn't matter.
這沒關系。
It was nothing at all.
根本沒關系。
It doesn't matter about the price.
價格沒關系。
It's alright,sir.
沒關系，先生。
thanks anyway.
沒關系，謝謝。
Yes, that's all right.
可以，沒關系。
Do not mention it.
不客氣。
You are very welcome.
不客氣。
Don't mention it.
不客氣。
You is welcome.
不客氣。
Offensive in manner.
不客氣的
Tax official: you are welcome.
稅務局：不客氣！
No trouble.
不客氣（沒有麻煩）。
Please do not mention it.
請不用客氣。
You're very welcome.
不用客氣。
His answer wants politeness.
他的回答不夠客氣。