全国pets二级完形填空试题

　　In September, in Britain, you may see a lot of birds 36 on roofs and telegraphwires．These birds are swallows．They are37together because, very soon, they will beflying 38 to much warmer lands, where they will find 39 small flying insects onwhich they 40There are no such insects 41 in Britain during the winter, as it is42．cold for them.

　　The swallows settle, fly off, swoop, and43 again．This they do many times, for theyare making short44 flights in order to be fit for the long journey45them.

　　46 of these migrating birds leave Britain in the autumn．They fly47for hundreds ofmiles48 they reach the warm lands of Africa．But not all the birds get there, for many ofthem perish in the stormy weather they meet with49.

　　In the spring of the following year they 50 the long and tiring journey back to Britain.

　　They return to the identical barn or tree in the51 district which they had left the52autumn.

　　How do these birds find their53 there and back over such vast distances? Nobody knows ex-actly54 , but it has something to do55 winds and air currents.

　　36.A.being perchedB.perchingC.being perchingD.be perched

　　37.A.gatheringB.assemblingC.waitingD.forming

　　38.A.to southB.the southC.to southwardsD.south

　　39.A.great number ofB.a great deal ofC.plenty ofD.numerous

　　40.A.feedB.are fedC.eatD.rely

　　41.A.nearB.aboutC.nearbyD.over

　　42.A.tooB.a bitC.veryD.much

　　43.A.fly offB.swoopC.settleD.turn back

　　44.A.practicalB.practicingC.practiceD.practised

　　45.A.in advanceB.ahead ofC.in front ofD.in front

　　46.A.SwarmsB.HerdsC.FlocksD.Schools

　　47.A.firmlyB.stoutlyC.harshlyD.steadily