5 . 阅读下面材料,在空白处填入适当的内容(1个单词)或括号内单词的正确形式。
The job of a scientist is to find out the 1 (true)in the field of science. It is a 2 (challenge)profession. Scientists usually have to do thousands of 3 (experiment)in order to prove something. 4 they are often disappointed if they fail, most of them never give up. My next door neighbor is a scientist, 5 studies radiation.
He is always working in his lab, 6 (try)to figure out all the mysteries that make him 7 (puzzle). When I met him the other day, he had just come back from work, looking excited. He told me he had had 8 breakthrough. He sounded so trilled. Then I noticed that he was wearing shoes that did not match. He must have been working 9 hard to notice! I think it's good to do a job that you are interested in. Otherwise you will get bored 10 (easy).