gainful

例句：

1. 1. The investment in renewable energy is gaining popularity among investors.
   对可再生能源的投资正在投资者中越来越受欢迎。
2. 2.The new software has proven to be gainful for our business.
   这款新软件对我们的业务非常有价值。
3. 3. Her advice was gainful to me, and I'll remember it for future reference.
   她的建议对我很有价值，我会记住并在未来参考。