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11017年10月托福考试阅读理解全真试题5
Question 39-50 Galaxies are the major building blocks of the too are made more manageable by using a time calibration， in this case the distance that light travels in one year. On such a scale the nearest giant spiral galaxy， the Andromeda galaxy， is two million light years away. The most distant luminous objects seen by telescopes are probably ten thousand million light years away. Their light was already halfway here before the Earth even formed. The light from the nearby Virgo galaxy set out when reptiles still dominated the animal world.
word "major" in line 1 is closest in meaning to
〔A〕 intense
〔B〕 principal
〔C〕 huge
〔D〕 unique
does the second paragraph mainly discuss？
〔A〕 The Milky Way
〔B〕 Major categories of galaxies
〔C〕 How elliptical galaxies are formed
〔D〕 Differences between irregular and spiral galaxies
word "which" in line 10 refers to
〔A〕 dust
〔B〕 gas
〔C〕 pattern
〔D〕 galaxy
to the passage， new stars are formed in spiral galaxies due to
〔A〕 an explosion of gas
〔B〕 the compression of gas and dust
〔C〕 the combining of old stars
〔D〕 strong radio emissions
word "