In the original test，all the animals in a test group are given a substance _______ half of them die
B
本题考查词义辨析。until：直到。符合句意，表示givenasubstance持续到halfofthemdie。
Manisa“victimofforcesoverwhichhehasnocontrol.”Thisisanotionheldstronglyby().
Most literary critics think that Fitzgerald is both an insider and an outsider of( )with a double vision.
In 1920,( )published his first novel This Side of Paradise which was,to some extent,his own story.
AftertheAmericanCivilWar,theliteraryinterestintheso-called“reality”oflifestartedanewperiodintheAmericanliterarywritingsknowantheAgeof().
MarkTwain’sparticularconcernaboutthelocalcharacterofaregioncameaboutas“localcolorism,”auniquevariationofAmericanliterary().