1.Its graduates do two jobs: representing the Holy See to the local government and keeping a vigilant eye on national churches.
该学院的毕业人员从事两大职责：在驻地政府代表圣座，并监督其国内各教会。
2.You will mix me up if you ask me to do two jobs at once.
如果你叫我同时做两样工作，你就会把我搞糊涂的。
3.Relative pronouns' do two jobs at once.
‘关系代名词’同时起两个作用。
4.To keep a large family, he has to do two jobs at the same time.
为了养活一大家子人，他不得不同时打两份工。