Here is what I would write if I had to do this, so my favorite animal is a dog so i would say
My favorite animal is a dog. I like dogs because they are fluffy. I also like dogs because you can pet some of them and they will not bite . Sometimes they will bite. I also like dogs because they can be different sizes and different breeds. They are sometimes nice and they can also be mean. But they are normally nice. I only like nice dogs because they do not hurt you.
