It's useless to regret what has been done.

后悔所做的事是没有用的。

It is no use regretting what has been done.

后悔做过的事情是没有用的。

What has been will be again, he said, and what has been done will be done again.

他说，已有的事，后必再有，已行的事，后必再行。

What has been will be again, what has been done will be done again; there is nothing new under the sun.

已有的事，后必再有。已行的事，后必再行。日光之下并无新事。--《旧·传》。

And just what has been done by the oiling and smoothing?

但是在车轮上涂油和把路修平有什么作用呢？

Let's say thank you to these people for what has been done.

让我们对这些曾经为亚澳做出贡献的人们说上一声“谢谢”。

I think other people can judge what has been done and make decisions.

我想其他人可以判断发生了什么，并得出结论。

This is not yet over, so no one can know the ultimate of what has been done.

现在的事件尚未结束，所以没有人能知道已采取的措施将带来的最终结果。

People have supported what has been done in Afghanistan but they are wanting an explanation of where we go next.

他说，“人们支持我们以前在阿富汗所做的，但他们想知道我们下一步将会如何行动。”

In mice and tobacco, this was overcome by over-expression of prolyl hydroxylase , analogous to what has been done in yeast and insect cell culture.

在小鼠和烟草中，这是通过过渡表达聚羟化酶来实现的，类似于酵母和昆虫细胞培养。