a futile attempt的用法和样例：
- I'm sure it will turn out a futile attempt.
- Soon after, the Jovians arrived on the scene and the Amarrians made a futile attempt to subjugate them, resulting in a humiliating defeat.
- Ill-informed investors who are very risk averse tend to place their assets in passbook savings accounts, certificates of deposit or Treasury Bills in a futile attempt to avoid all risk.
- I saw Chinese troops needlessly applying the torch to whole blocks of homes and shops around the city walls, dispossessing thousands in a futile attempt to impede the Japanese attack.
- She turned on the radio with a futile gesture.