He said he acted for the students in bringing out such a plan.

【翻译】他说，他代表学生提出了这个计划。

【分析】可能是曹老师疏忽了，句中的acted 不是ached。

1. act for：意为“代理(某人职务)，代办，代为(处理某事)；代表，作…代言人，作…的代理人”。

例如：His secretary will act for him in all his affairs. 他的秘书将代他处理他的全部事务。本句的in all his affairs，意为“在他的全部事务方面”代他处理，介词短语看作“方面状语”。

2. in bringing out such a plan，也是方面状语，表示“在......方面”代表学生。

bring out 意为“提出；说出；发表”。

3. 关于act for 的用法，再举数例：

Please act for me during my absence. 在我外出期间，请代理我的职务。

He acted for the general manager who was ill. 总经理病了，工作由他代理。

He acted for Smith while he was away. 史密斯不在时，由他代理（史密斯的工作）。

Since he fell ill, his daughter has been acting for him in all his affairs. 自他病倒以来，他女儿一直代他处理着他的全部事务。