Affirmative +
There is/there are + what + where
sg
There is/there’s a chair on the right. (a/an+sg countable nouns)
There is/there’s some milk in the fridge. (some + uncountable nouns)
pl
There are some plants on the windowsill. (some + pl nouns)
Negative –
sg
There isn’t a chair on the right.
There isn’t any milk in the fridge. (any+ uncountable nouns) (= There is no milk in the fridge).
pl
There aren’t any plants on the windowsill .(any+ pl countable nouns) (=There are no plants on the windowsill)
Question ?
sg
Is there a chair on the right?
Is there any milk in the fridge? (any+ uncountable nouns)
pl
Are there any plants on the windowsill? (any+ pl countable nouns)
Short answer
sg
Yes, there is./ No, there isn’t.
pl
Yes, there are./ No, there aren’t.
Special Question ?
sg
What is there on the right/in fridge/on the windowsill?