ls there a+名词单数+介词短语?肯定回答: Yes, there is.
否定回答:No,there isn't.
Are there any +名词复数+介词短语?肯定回答: Yes, there are.
否定回答:No,there aren't.

地点介词+限定词+名词
in my room
under the sofa
under the desknext to the mapon the floor
behind the desk
on the wall
beside the table
behind the door on the windowin front of the clock

Underline these sentences(给这些句子划线)
1 Look at my bedroom for oneminute.
2 Are there any balls?
Yes.They are under the desk.3 ls there a computer in my room?Yes, there is.On the desk.