“Cool” is a word with many meanings, ____  As the world change, the word has many different meanings.
   “Cool” can be used to express feelings of interest in almost anything. When you see a famous car on the street, maybe you will say, “It’s cool.” ____  You can use “cool” instead of many words. ____  A teacher asked her students to write about the waterfall(瀑布) they had visited.On one student’s paper was just one sentence,“ It’s so cool.”____  But the story also shows a scarcity(缺乏) of words. Without “cool”, some people have no words to show the same meaning. ____ I can. And I think they are also very cool.