effort是一个常见的英语单词，意思是努力或尝试。它是一个非可数名词，因此不需要在单数形式中添加“-s”或“-es”来表示复数。但是，我们在使用名词量词（如a，an，some和many）时需要注意。下面是一些例子：
- He made a great effort to finish the project on time. (正确)
- He made great efforts to finish the project on time. (正确)
- He made a efforts to finish the project on time. (错误)
- He made some effort to improve his English. (正确)
- He made many effort to improve his English. (错误)
除了作为名词之外，effort还可以作为动词，意为“努力做”，例如：
- We should effort to learn something new every day. (正确)
- We should efforts to learn something new every day. (错误)
在学习英语中，了解名词单词是否可数以及如何使用量词是非常重要的，这有助于准确地表达你的意思。