Oraciones con there is y there are[negative y interrogative}?

Oraciones con there is, there are , there was, there were afirmativa negativa y interrogativa?

There is : afirmativa : There is a cow. Negativa : There isn't a cow. Interrogativa : Is there a cow? There are : afirmativa : There are some cows. Negativa : There aren't some cows. Interrogativa : Are there some cows?…