完形填空

　　Colour helps you see things．But man and some monkeys and apes(猿) are the only mammals(哺乳动物) that can see colour．1 　 any other mammals，such as the dog，the world 2 　 a black-white photo．Dogs hunt mainly by listening and smelling．

　　Like 3 　 animals，dogs see best when things move．The animals they hunt seem to know this．A rabbit or deer will freeze when they find that they are being hunted．Then the dog 4 　 see it at all

　　Birds can see colour．They need to，because when they fly，they need to find places to land．Colour helps them know 5 　 the place is and what it is like so that they are able to catch flying things in the air or to 6 　 something they think safe．

　　Some birds see things even 7 　 than man．The birds that eat bugs(虫子) can see them from far away．And even a very young bird can see a house 8 　 the sky．So good eyes and being able to see colours help birds 9 　 food and also help them find out 10 　 there are other animals that are dangerous to them．

(1)

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)