在
Paragraph 2: Outflow channels are probably relics of catastrophic flooding on Mars long ago. They appear only in equatorial regions and generally do not form extensive interconnected networks. Instead, they are probably the paths taken by huge volumes of water draining from the southern highlands into the northern plains. The onrushing water arising from these flash floods likely also formed the odd teardrop-shaped “islands” (resembling the miniature versions seen in the wet sand of our beaches at low tide) that have been found on the plains close to the ends of the outflow channels. Judging from the width and depth of the channels, the flow rates must have been truly enormous—perhaps as much as a hundred times greater than the 105 tons per second carried by the great Amazon river. Flooding shaped the outflow channels approximately 3 billion years ago, about the same times as the northern volcanic plains formed. 【TPO8- Running Water on Mars?】
3. The word “relics” in the passage is closest in meaning to
○ remains
○ sites
○ requirements
○ sources
4. The word “miniature” in the passage is closest in meaning to
○ temporary
○ small
○ multiple
○ familiar
答案：(1)(2)
以上就是小编为