Question

singular and plural nouns 1. We keep sheep to get wool​

Answer 1

it is already in prural

singular:

we keep a sheep to get wool.

Answer 2

Answer:

This is a plural noun already. Sheep itself is plural but if you want to stress more on it, you can write that we keep hordes of sheep to get wool.

The plural of sheep is also sheep so there is no change that will be required to make it plural whatsoever.