Rhinos are some of the largest animals in the world. They live in Africa and Asia in tropical rain (1) ............ and grasslands. The biggest (2) ............ can weigh 2,400 kilos, which is the weight of thirty men. Although they are very big and strong, they don’t (3) ............ other animals, but instead they feed on lots of grass and other plants. In fact, they spend all day and night eating. What rhinos really love is being in or near water, where they can (4) ............ cool. They generally live on their own, except for the (5) ............ relationship they have with oxpeckers. These are small birds that sit on rhinos and help keep them free of insects. Rhinos only have one (6) ............ - humans, who kill them to take their horn. Since the beginning of the 20th century their population has fallen from 500,000 to only 29,000 now living in the wild.