练习材料
Lesson 43-1 Are there strangers in space?
We must conclude from the work of those who have studied the origin of life, that given a planet only approximately like our own, life is almost certain to start. Of all the planets in our own solar system, we are now pretty certain the Earth is the only one on which life can survive. Mars is too dry and poor in oxygen, Venus far too hot, and so is Mercury, and the outer planets have temperatures near absolute zero and hydrogen-dominated atmospheres. But other suns, stars as the astronomers call them, are bound to have planets like our own, and as the number of stars in the universe is so vast, this possibility becomes virtual certainty. There are one hundred thousand million stars in our own Milky Way alone, and then there are three thousand million other Milky Ways, or galaxies, in the universe. So the number of stars that we know exist is now estimated at about 300 million million million.
/ˈlɛsən/ 43-1 /ɑr/ /ðɛr/ /ˈstreɪnʤərz/ /ɪn/ /speɪs/?
/wi/ /məst/ /kənˈklud/ /frəm/ /ðə/ /wɜrk/ /əv/ /ðoʊz/ /hu/ /həv/ /ˈstʌdid/ /ði/ /ˈɔrəʤən/ /əv/ /laɪf/, /ðæt/ /ˈgɪvən/ /ə/ /ˈplænət/ /ˈoʊnli/ /əˈprɑksəmətli/ /laɪk/ /ˈaʊər/ /oʊn/, /laɪf/ /əz/ /ˈɔlˌmoʊst/ /ˈsɜrtən/ /tə/ /stɑrt/. /əv/ /ɔl/ /ðə/ /ˈplænəts/ /ɪn/ /ˈaʊər/ /oʊn/ /ˈsoʊlər/ /ˈsɪstəm/, /wi/ /ər/ /naʊ/ /ˈprɪti/ /ˈsɜrtən/ /ði/ /ɜrθ/ /əz/ /ði/ /ˈoʊnli/ /wʌn/ /ɑn/ /wɪʧ/ /laɪf/ /kən/ /sərˈvaɪv/. /mɑrz/ /ɪz/ /tu/ /draɪ/ /ənd/ /pur/ /ɪn/ /ˈɑksəʤən/, /ˈvinəs/ /fɑr/ /tu/ /hɑt/, /ənd/ /soʊ/ /əz/ /ˈmɜrkjəri/, /ənd/ /ði/ /ˈaʊtər/ /ˈplænəts/ /həv/ /ˈtɛmprəʧərz/ /nɪr/ /ˈæbsəˌlut/ /ˈzɪroʊ/ /ənd/ /ˈhaɪdrəʤən/-/ˈdɑməˌneɪtəd/ /ˈætməˌsfɪrz/. /bət/ /ˈʌðər/ /sʌnz/, /stɑrz/ /əz/ /ði/ /əˈstrɑnəmərz/ /kɔl/ /ðɛm/, /ɑr/ /baʊnd/ /tə/ /həv/ /ˈplænəts/ /laɪk/ /ˈaʊər/ /oʊn/, /ənd/ /əz/ /ðə/ /ˈnʌmbər/ /əv/ /stɑrz/ /ɪn/ /ðə/ /ˈjunəˌvɜrs/ /ɪz/ /soʊ/ /væst/, /ðɪs/ /ˌpɑsəˈbɪləti/ /bɪˈkʌmz/ /ˈvɜrʧuəl/ /ˈsɜrtənti/. /ðər/ /ər/ /wʌn/ /ˈhʌndrəd/ /ˈθaʊzənd/ /ˈmɪljən/ /stɑrz/ /ɪn/ /ˈaʊər/ /oʊn/ /ˈmɪlki/ /weɪ/ /əˈloʊn/, /ənd/ /ðɛn/ /ðər/ /ər/ /θri/ /ˈθaʊzənd/ /ˈmɪljən/ /ˈʌðər/ /ˈmɪlki/ /weɪz/, /ɔr/ /ˈgæləksiz/, /ɪn/ /ðə/ /ˈjunəˌvɜrs/. /soʊ/ /ðə/ /ˈnʌmbər/ /əv/ /stɑrz/ /ðət/ /wi/ /noʊ/ /ɪgˈzɪst/ /əz/ /naʊ/ /ˈɛstəˌmeɪtəd/ /ət/ /əˈbaʊt/ 300 /ˈmɪljən/ /ˈmɪljən/ /ˈmɪljən/.
