没事儿。/别放在心里!
That's all right. *有时连写成That's alright.
I'm sorry. (对不起。)
That's all right. (没事儿。/别放在心里!)
Don't worry about it.
Don't worry.
It's no big deal. (不是什么大不了的事。)
Never mind.
I forgot to bring your book. (我忘了把你的书带来了。)
Never mind. (不必在意。)
下次要多加小心。
Please be more careful next time.
。