我知道他未完成这项工作，但毕竟他尽力了。

I know he hasn't finished the work, but after all, he's done his best.

youdao

他已经尽力在物质和精神上帮助这个孩子了。

He has tried to help this child materially and spiritually.

《柯林斯英汉双解大词典》

我知道他已经尽力了，尽管如此，他的工作仍不太理想。

I know that he has tried hard; be that as it may, his work is just not good enough.

《牛津词典》

Now, that's actually a difficult question to ask-- to answer for a child, but I tried my best to give him an answer.

向一个孩子解释这个问题其实挺困难的，但我还是尽力给了他一个答案。

耶鲁公开课 - 心理学导论课程节选