Cockatoos are recognisable by the showy crests and curved bills. Their plumage is generally less colourful than that of other parrots, being mainly white, grey or black and often with coloured features in the crest, cheeks or tail.
An animal with long legs, that eats grass, leaves, etc. and can run fast. Most male deer have antlers (= horns shaped like branches). There are many types of deer.
An African or Asian animal like a deer, that runs very fast. There are many types of antelope. An antelope is a member of a number of even-toed ungulate species indigenous to various regions in Africa and Eurasia.