_ of us is working hard to make our country richer and stronger. A.Each B.Every C.Every one

every重点在“大家一致”,而each重点在“各有不同”,如every one of us(我们中
的每一个人)中的us（我们）是泛指,each of us（我们中的每一个）中的us（我
们）比较明确肯定.
例如：Each of us has his likes and dislikes我们各有各
的好恶.
这里城市里我们中的每一个人都努力工作从而使国家更富强,大家的重点是一致的,所以用every one.
另外不能混淆了everyone与every one的用法
everyone与every one
(1)everyone：everybody是代词,是“每个人；人人；大家”的意思,不指具体哪一个人,作主语时,谓语用第三人称单数形式.如：
Everyone can do it．谁都可以做此事.
Everyone is here except Tom．除汤姆外大家都到了.
(2)everyone只能指人,不能指物；every one既可指人,也可指物.如：
Every one／Everyone in our class likes playing football．我们班人人喜欢踢足球.
There is something wrong with every one of the bikes．每辆自行车都有毛病.
(3)every one可以和of连用构成短语,而everyone则不能.如：
Every one of us is getting ready for the exam．我们每个人都在为考试做准备.