In a class, studentsfirsttakepart in a preliminaryactivitythatintroduces the topic (i.e., orderingfood), the situation, and the
scriptthatwillsubsequentlyappear in a roleplay. Then the studentswork in pairswithfoodordering. Assessment is primarilybased on whether the intendedmeal is successfullyorderedratherthan on the accuracy of languageforms. This is an example
(A) the audiolingualmethod (B) the directmethod (C) task-basedinstruction (D) form-based instruction
Many of the mostdamaging and life-threateningtypes of weather - torrentialrains, severethunderstorms, and tornadoes - beginquickly, strikesuddenly, and dissipaterapidly, devastatingsmallregionswhileleavingneighboringareasuntouched. One suchevent, a tornado, stuck the northeasternsection of Edmonton, Alberta, in July 1987. Totaldamagesfrom the tornadoexceeded $250 million, the highestever for any Canadianstorm. Conventionalcomputermodels of the atmospherehavelimitedvalue in predictingshort - livedlocalstormslike the Edmontontornado, because the availableweatherdata are generally not detailedenough to allowcomputers to discern the subtleatmosphericchangesthatprecedethesestorms. In mostnations, for example, weather -balloonobservations are takenjustonceeverytwelvehours at locationstypicallyseparated by hundreds of miles. Withsuchlimiteddata, conventionalforecastingmodels do a muchbetter job predictinggeneralweatherconditionsoverlargeregionsthanthey do forecastingspecificlocalevents.
Untilrecently, the observation - intensiveapproachneeded for accurate, veryshort - rangeforecasts, or "Nowcasts," was not feasible. The cost of equipping and operatingmanythousands of conventionalweatherstations was prohibitivelyhigh, and the difficultiesinvolved in rapidlycollecting and processing the raw weatherdatafromsuch a networkwereinsurmountable. Fortunately, scientific and technologicaladvanceshaveovercomemost of theseproblems. Radarsystems, automatedweatherinstruments, and satellites are all capable of makingdetailed, nearlycontinuousobservationoverlargeregions at a relatively low cost. Communicationssatellites can transmitdataaround the worldcheaply and instantaneously, and moderncomputers can quicklycompile and analyzingthislargevolume of weatherinformation. Meteorologists and computerscientists now worktogether to designcomputerprograms and videoequipmentcapable of transforming raw weatherdataintowords, symbols, and vividgraphicdisplaysthatforecasters can interpreteasily and quickly. As meteorologistshavebegunusingthese new technologies in weatherforecastingoffices, Nowcasting is becoming a reality.
【題組】33. Why does the authorstate in line 10 thatobservations are taken "justonceeverytwelvehours?"
(A) To indicatethat the observations are timely (B) To show why the observations are on limitedvalue (C) To comparedatafromballoons and computers (D) To give an example of internationalcooperation
Birdsthatfeed in flockscommonlyretiretogetherintoroosts. The reasons for roostingcommunally are not alwaysobvious, but there are somelikelybenefits. In winterespecially, it is important for birds to keepwarm at night and conservepreciousfoodreserves. One way to do this is to find a shelteredroost. Solitaryroostersshelter in densevegetation or enter a cavity - hornedlarks dig holes in the ground and ptarmiganburrowintosnowbanks - but the effect of sheltering is magnified by severalbirdshuddlingtogether in the roosts, as wrens, swifts, browncreepers, bluebirds, and anis do. Bodycontactreduces the surfaceareaexposed to the cold air, so the birdskeepeachotherwarm. Two kingletshuddlingtogetherwerefound to reducetheirheatlosses by a quarter and threetogethersaved a third of theirheat.
The secondpossiblebenefit of communalroosts is thatthey act as "informationcenters." During the day, parties of birdswillhavespread out to forageover a verylargearea. Whentheyreturn in the eveningsomewillhave fed well, but others may havefoundlittle to eat. Someinvestigatorshaveobservedthatwhen the birds set out againnextmorning, thosebirdsthat did not feedwell on the previous day appear to followthosethat did. The behavior of common and lesserkestrels may illustratedifferentfeedingbehaviors of similarbirdswithdifferentroostinghabits. The commonkestrelhuntsvertebrateanimals in a small, familiarhuntingground, whereas the verysimilarlesserkestrelfeeds on insectsover a largearea. The commonkestrelroosts and huntsalone, but the lesserkestrelroosts and hunts in flocks, possibly so one bird can learnfromotherswhere to findinsectswarms.
Finally, there is safety in numbers at communalroostssincetherewillalways be a few birdsawake at any givenmoment to give the alarm. But thisincreasedprotection is partiallycounteracted by the factthatmassroostsattractpredators and are especiallyvulnerable if they are on the ground. Eventhose in trees can be attacked by birds of prey. The birds on the edge are at greatestrisksincepredatorsfind it easier to catchsmallbirdsperching at the margins of the roost.
【題組】13. The authormentionskinglets in line 9 as an example of birdsthat (A) protectthemselves by nesting in holes.
(B) Nestwithotherspecies of birds (C) Nesttogether for warmth (D) Usuallyfeed and nest in pairs.