这些形容词均含有“有益的，有利的”之意。

beneficial : 侧重对健康、身心或事业有益。

• A good diet is beneficial to health.
  良好的饮食有益于健康。
• A half-hour daily walk can be more beneficial than one hard bout of exercise a week.
  每天散步半小时会比一周剧烈运动一次对身体更有益。

advantageous : 多指能直接导致相对优势或有助于达到目的的事。

• advantageous interest rates
  有利可图的利率
• The lower tax rate is particularly advantageous to poorer families.
  低税率对于较为贫困的家庭尤其有利。

profitable : 多用于指能获得实用的或可获利的事。

• Over the years it has developed into a highly profitable business.
  经过这些年，它发展成了高盈利企业。
• I made profitable use of my time (= used my time to get advantages or benefits), mixing with a lot of different people and practising my Spanish.
  我充分利用时间和许多不同的人交往，练习我的西班牙语。