摘要： It is obvious that on no account to the teacher that he has done the homework on his own. A. this is the first time he is lying B. this is the first time he has lied C. is this the first time has he lied D. is this the first time he has lied Section B Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need. A. recently B. forming C. locate D. primitive E. fascinated F. evidence G. volcanic H. chemicals I. created J. closely Since early times, people have been 41 with the idea of life existing somewhere else besides earth. Until recently, scientists believe that life on other planets was just a hopeful dream. But now they are beginning to 42 places where life could form. In 1997, they saw 43 of planets near other stars like the sun. But scientists now think that life could be even nearer in our own solar system. One place scientists are studying very closely is Europa, a moon of Jupiter. Space probes have provided evidence that Europa has a large ocean under its surface. The probes have also made scientists think that under its surface Europa has a rocky core giving off 44 heat. Water and heat from volcanic activity are two basic conditions needed for life to form. A third is certain basic 45 such as carbon, oxygen and nitrogen. Scientists believe there might be such chemicals lying at the bottom of Europa’s ocean. They may have already 46 life or may be about to. You may wonder if light is also needed for life to form. Until 47 , scientists thought that light was essential. But now, places have been found on earth that are in total blackness such as caves several miles beneath the surface. And bacteria, 48 forms of life, have been seen there. So the lack of light in Europa’s sub-surface ocean doesn’t automatically rule out life 49 .

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