beneficial 
英 [ˌbɛnɪˈfɪʃəl]  美 [ˌbɛnəˈfɪʃəl] 
adj. 有益的；有利的；有帮助的；受益的

例句：
He had a beneficial influence on the children. 

他对孩子们产生了有益的影响。

Using computers has a beneficial effect on children's learning. 

使用计算机对孩子们的学习有益。

Wine in moderation is beneficial to health. 

适量饮酒有益健康。

to have a beneficial effect on sth 

对…有益；有益于…