"A puppy is fun."
Translation:Tha cuilean spòrsail.
Native English speaker here, "A puppy is fun," sounds natural enough me, but it is an unusual sentence. General statements about some thing in English usually take the plural, just like "statements" was in this sentence. Thus I would expect to see, "Puppies are fun."
However, I can also say, "A general statement sometimes uses a singular-form subject."