effortu可數(shù)嗎

　　I made every effort to be cooperative.

　　我盡力配合。

　　I'm afraid this essay is a poor effort.

　　很抱歉，這篇文章寫得不好。

　　He spared no effort to make her happy again.

　　為使她重新快樂起來，他想盡了辦法。