A. double-decker B. boredom C. fragment D. empty A. clean the room B. unit C. reduce D. perch A. food for thought B. pencil case C. smaller D. display A. pollute B. youth C. become D. memorize A. status B. organic C. fine D. drinking A. delicacy B. think highly of C. have in common D. allow A. foundations B. turn to C. form D. quicken A. listeria B. rich C. overnight D. abolish A. Beijing Opera B. look forward to C. stressful D. punish A. walker B. simple C. insure D. hear of