well done意思是干得好。

一般情况下是一种"感叹"的语气，当别人某件事干得漂亮时所给予的夸奖。well done在吃牛排时，是形容牛排全熟。

例句

When I found my son raised his hand and started call out wildly, "Well done, Mickey!" 

当我发现我儿子举起手开始疾呼：“干得好！米奇！”

Please give me a hamburger, well done. 

请给我一份熟透的汉堡牛排。

He observed to me that our work was very well done. 

他对我说我们的工作做得很好。