Theflowerbudofawaterlily百合opensatsunsetsince.itsopeningistriggered(commence).bythedecreasedlight.

• A.alleviated减轻
• B.endured
• C.setoff
• D.coveredup

Thefearofsmallpox,whichterrorizedtheeighteenthcentury,hasnoanalogy(likeness)today.

• A.occurrence
• B.remnants残留物
• C.witnesses
• D.parallel

Despitetheproliferationofotherfastermodesoftransportation,therailroadsremainthelargestcarriersofintercityfreightintheUnitedStates.

• A.schemes
• B.means
• C.tracks
• D.variables

HowmanypeopleareawarethatadancerwiththeNewYorkCityBallettypicallywearsoutaminimumoftwohundredpairsoftoeshoesperyear?

• A.only
• B.exactly
• C.atleast
• D.fewerthan

ThefirstimportantexpositionintheUnitedStateswasheldinPhiladelphiain1876.

• A.exhibition
• B.concert
• C.excursion
• D.contest

Thedoctorshareshisphonenumberwiththepatients__________theyneedmedicalassistance.

• A.ifonly
• B.asif
• C.eventhough
• D.incase