区别就是两者意思是不一样，具体的不同如下
Is she中文意思是她是……
"Is she coming back?"—"Maybe. No one hears from her."
areyou中文意思是你是你们是是吗
You're joking. Are you serious?你在开玩笑吧。你是认真的吗
Are you collecting for charity?
区别是：
are的主语是复数或者第二人称。
is的主语是第三人称单数。
例句：
are
1、Jim and I are getting married.
我和吉姆就要结婚了。
2、You have to admit that you are， in fact， in difficulties.
你不得不承认，你事实上是陷入了困境。
3、We are cognizant of the problem.
我们意识到了这个问题。
is
1、Clearly there is a problem here.
显然，这里出了个问题。
2、This is a common fallacy which has no basis in fact.
这是一个没有事实依据的常见谬误。
3、Choosing the right type of paint for the job is half the battle.
选对了涂料，这项工作就成功了一半。
