there be
意思：表示存在或者发生。
英文释义：used to show that sth exists or happens
如果现在进行时，单数时用is，复数时用are。
现在我问你一个问题.
How many students in the class room?
你怎么回答呢？
使用there be 句型来回答如下：
There is a
student in the classroom.
有一个学生在教室里边。
There are five students in the class
room. 有五个学生在教室里边。
假如我想说有五个学生和一个老师在教室里，怎么说呢？那当然是：
There are five students and one teacher in the classroom.
假如说我把学生和老师的位置换一下呢，这时就要用is了，因为there be 遵循就近原则。
必须这样说：
There is one teacher and five students in the classroom.
如果是过去式呢，只需将is换成was，are换成were即可。
There was one student in the classroom yesterday.
There were five students int the classroom yesterday.
原文：http://www.cnblogs.com/sdlypyzq/p/3705368.html