effort：
n.气力;努力;费力的事;艰难的.尝试;试图;尽力;有组织的活动；
复数： efforts
例句：
The project has demanded considerable investment of time and effort.
该项目已让我们投入了相当多的时间和精力。
We need to make a concerted effort to finish on time.
我们需要通力合作才能按时完成。
The local clubs are making every effort to interest more young people.
地方俱乐部正在尽一切努力来吸引更多的年轻人。