1. Their efforts are rewarded.
2. Their efforts have been rewarded.
3. They have made a lot of effort to overcome the obstacles.
4. They have put in a lot of effort to achieve (such) good school results.
5. They have put a lot of effort into achieving good school results.
Despite all their efforts, the rescue team were unable to save the drowning animal.
Despite all my efforts, I was not able to persuade even one of them to ...