请排列下列句子的顺序，使语意连贯。

①前面出现了水闸，等着他去推动发电机。

②再前面又出现了城市。

③小河很快就把乌鸦丢在后面，又不住地往前奔流。

④小河高高兴兴地做了一切他该做的工作。

正确的排列顺序是：____

    Many people are interested in talking about life in the future. Some people 1 that life in the future will be easier and more comfortable. But others believe that it will be worse and more difficult than now. As for me, I 2 the idea of the first team.

    First，as for education, people will have 3 education .This is because of technology (科技). E-books will replace (取代) common books, robots will replace teachers, and students will not have to go to school every day. They will 4 at home through online teaching and will find learning more interesting.

    Second, people' s 5 will improve. Technology will also play a very important role. New medicine will help people get better quickly. Robots will help doctors and sometimes replace 6 Also, doctors will be able to cure more diseases (治愈更多疾病), 7 people will live longer.

    Third, housing problems will end. People will build houses under the sea. Also, some people will live 8 the moon. Then everyone will have a place to live.

    Fourth, hunger will stop all over the world. People will grow crops (庄稼) everywhere 9 on the top of buildings.

    Now what about you? 10 do you think life in the future will be like?

结合语境，补写句子，使之与前后句子构成排比。

       如果你是鱼儿，那快乐就是一汪清凉的水；如果你是小草，那快乐就是一束暖香的阳光；如果你是____，那快乐就是____；如果你是____，那快乐就是____。