Read the text and fill in the gaps with the correct grammatical forms.

Why do people keep cats as pets? Cat owners ... that cats make excellent friends. Cats ... playful, clever and loving animals. They can also be left alone for several days at a time. This is why millions of people today choose to share ... homes with cats. People have kept cats as pets for the longest time. Ancient Egyptians ... keeping cats as pets more than 4,000 years ago. But first they liked cats because wild cats were keeping animals like ... and rats away from their food. Ancient Egyptians also took cats with them on hunting trips.