1. act as (临时)担任,充当,起……的作用。如:A trained dog can act as a guide to a blind person. 经过训练的狗可以担任盲人的向导。表示担任独一无二的职务,其前通常不用冠词。如:He acted as manager in my absence. 我不在时他担任经理。I don’t understand their language; you’ll have to act asinterpreter. 我不懂他们的语言,你得当翻译了。 2. act for 代理(某人职务),代为(处理某事)。如:Please act for me during my absence. 我不在时请代理我处理事务。I acted for our captain while he was in hospital.