四级完形填空(含答案说明)—ClozeTest20.docx

四级完形填空(含答案说明)—ClozeTest20
Today, most countries in the world have countries have bu









四级完形填空(含答案说明)—ClozeTest20
Today, most countries in the world have countries have built canals near the coast, and parallel 1 the in the twentieth century, goods can be moved more cheaply by boat than by any other 2 of 　　3 make it possible for boats to travel 4 ports along the coast without being 5 to the dangers of the canals, such as the Suez and the Panama, save ships weeks of time by making their 6 a thousand miles canals permit boats to reach cities that are not 7 on the coast, still other canals 8 landsswheresthere is too much water, help to 9 fields wherethere is not enough water, and 10 water power for factories and size of a canal 11 on the kind of boats going through canal must be wide enough to permit two of the largest boats using it to 12 each other must be deep enough to leave about two feet of water 13 the keel of the largest boat using the the planet Mars was first 14 through a telescope, people saw that the round disk of the planet was criss-crossed by a 15 of strange blue-green were called