Italian plurals : definite articles

What is the correct plural of the word il libro - change to the books?

Make the word plural: la ragazza

Make the word plural :
la scuola =

Make the word the pen plural: la penna =

Make the word for butterfly plural: la farfalla =

Make the word for the door plural: la porta =

Make the word for the teacher plural:
la maestra =

Make the word for the aunt plural :

la zia =

Make the word the boy plural = il ragazzo

Make the word the grandfather plural = il nonno