2）Can you make animals w______ for us?Some scientists think that one day we can teach a________
to do a lot of work for people.They say that in a f________ or on TV,you may see elephants,monkeys,tigers or some other animals always have a little f______ to eat after they do something.Scientists say that people can teach m______ different animals to do some of the work when they know they will get something to e______.We all k______ elephants can carry large things,and d______ can look after houses.And we can teach animals to work in factories.In America,for example,people t________ apes to make cards,and scientists think that those b________ monkeys may drive trains one day.
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