done his duty

• v. 尽职(尽本分；尽义务)

done his duty的用法和样例：

例句

1. He knew where his heart lay, but where did his duty lie? And so did he toss and turn, and get up for a drink of water, and knock over a pile of books.
   他知道他的良心何在。但是责任何在呢？这个问题使他辗转难眠，起床去喝水，结果打翻了一摞书。