第十三篇

　　Today, most countries in the world have canals.Many countries have built canals near the coast, and parallel __1__ the coast.Even in the twentieth century, goods can be moved more cheaply by boat than by any other __2__ of transport.These __3__ make it possible for boats to travel __4__ ports along the coast without being __5__ to the dangers of the open.Some canals, such as the Suez and the Panama, save ships weeks of time by making their __6__ a thousand miles shorter.Other 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 mills.The size of a canal __11__ on the kind of boats going through it.The canal must be wide enough to permit two of the largest boats using it to __12__ each other easily.It must be deep enough to leave about two feet of water __13__ the keel of the largest boat using the canal.When 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 lines.These were called“canals” __16__ they looked the same as canals on earth __17__ are viewed from an airplane.However, scientists are now __18__ that the Martian phenomena are really not canals.The photographs __19__ from space-ships have helped us to __20__ the truth about the Martia“canals”.

　　1.A.off B.with C.to D.by

　　2.A.way B.means C.method D.approach

　　3.A.waterways B.waterfronts C.channels D.paths

　　4.A.among B.between C.in D.to

　　5.A.revealed B.exposed C.opened D.shown

　　6.A.trip B.journey C.voyage D.route

　　7.A.lain B.stationed C.set D.located

　　8.A.escape B.drain C.dry D.leak

　　9.A.water B.wet C.soak D.irrigate

　　10.A.furnish B.afford C.offer D.give

　　11.A.focuses B.bases C.depends D.takes

　　12.A.cross B.pass C.move D.advance

　　13.A.down B.below C.beneath D.off

　　14.A.studied B.researched C.surveyed D.observed

　　15.A.few B.number C.deal D.supply

　　16.A.although B.because C.so D.if

　　17.A.that B.where C.when D.as

　　18.A.exact B.definite C.certain D.decisive

　　19.A.held B.taken C.got D.developed

　　20.A.find B.expose C.uncover D.discover

　　第十三篇答案+解說:

　　1.【答案】C

　　【解析】parallel to“與……平行”，固定搭配。

　　2.【答案】B

　　【解析】means of transport“交通工具”，固定搭配。

　　3.【答案】A

　　【解析】waterways“水道”;waterfronts指城市的濱水區(qū);channels指海峽;paths指小路。

　　4.【答案】B

　　【解析】between指在兩個港口間航行。among指三個或三個以上。