经济利益不应该是唯一的动机。

Financial ___gain should not be the only motivation.

在效率和成本降低方面取得了巨大收益。

There are huge ___gains in terms of efficiency and cost reduction.

志愿活动带来的个人收获往往是无形的但很有价值。

The personal ___gain from volunteering is often intangible but valuable.