volunteer for special duty

• 自告奋勇

volunteer for special duty的用法和样例：

例句

1. Several mice offered themselves for this mission.
   有几只老鼠自告奋勇地承担了这一任务。
2. If an errand had to be run, she was always the first volunteer.
   如果有什么差事要跑跑腿的话，他总是第一个自告奋勇者。