6、ce.A.takeoverB.showoffC.showupD.giveup12.Notuntilitwasdark______,whichmadehismotherworried.A.didheshowupB.heshowedupC.hehasshowedupD.hasheshowedup13.Itwillbealongtime____Frank____backfromabroad.A.since,hascomeB.before,comesC.when,cameD.after,hascome14.__________ my si
7、ster three times today but her line was always busy. A.I’d phoned B.I’ve been phoning C.I’ve phoned D.I was phoning 15.I won’t tell the student the answer to the math problem until he______ on it for more than an hour. A.has been working, B
8、.will have worked C.will have been working D.had worked16.Tom____someJapanesewhilehewasawayonbusinesstripinJapan.A.to