There is---> Singular
There is a red apple
There is a beautiful cat
There is a beautiful boy
There is a rabbit in house
There is a beautiful dress
There is a ball in house
There is a baby
There is purple shirt
There is a teacher in the class
There is a girl with pretty eyes
There are ---> Plural
There are many books
There are many black shoes
There are many cookies
There are many apples
There are many notebooks
There are many yellow pencils
There are children in the parkIn the sea there are many fish
There are many monkeys in the zoo
There are many children in the school
There was ---> Singular
There was red apple
There was a beautiful cat
There was beautiful boy
There was a rabbit in house
There was a beautiful dress
There was a ball in house
There was a baby
There was purple shirt
There was is a teacher in the class
There was a girl with pretty eyes
There Were ---> Plural
There were many books
There were many blacks shoes
There were many cookies
There were many apples
There were many notebooks
There were yellow pencils
There were children in the parkIn the sea there were are many fish
There were many monkeys in the zoo
There were many children in the school
Espero haberte ayudado! Saludosxoxs