Question

transform these sentences into the plural

he is a good father

she is an excellent doctor

peter is a good brother

she is an American  singer

it is an english book

I am a tall boy

My father is an engineer

That car is very fast

That toy is expensive

The ball is new

Answer 1

Basicamente solo tienes que cambiar el pronombre con "They" ya que significa Ellos y Ellas y sirve para los dos. Y si son objetos puedes poner "Those" que es That en plural.

-They are good fathers.

-They are excellent doctors.

-They are good brothers.

-They are American singers.

-Those are the english books.

-They are tall boys.

-My parents are engineers.

-Those toys are expensive.

-The balls are new.

 

Answer 2

He is a good father  ->   They are good fathers.

 

She is an excellent doctor   ->  They are excellent doctors.

 

Peter is a good brother      ->  They are good brothers.

 

She is an American  singer   -> They are American singers.

 

It is an english book   ->  They are english books.

 

I am a tall boy   ->  We are tall boys.

 

My father is an engineer    ->  Our fathers are engineers.

 

That car is very fast   ->  Those cars are very fast.

 

That toy is expensive   ->  Those toys are expensive.

 

The ball is new  -> The balls are new.

 

*NOTA:  Recuerda que en inglés los adjetivos no tienen ni género ni número, excepto los de cantidad y los demostrativos.

 

Demostrativos:

 

Singular        Plural

That       --->    those

This      ---->    these

 

~Espero que te sirva :)