there be句式中动词be的变体英语语法 单数is，复数are，如：There is a table in the room. 房间里有一张桌子。There are some birds in the tree. 树上有很多鸟。1.There is+单数可数+地点状语例：There is a ruler on the desk. 书桌上有一把尺。2.There are+单数可数+地点状语例：There are four apples on the tree. 树上有四个苹果。There are some flower
