A. let's B. commercialization C. vowel D. teaching A. vulgar B. enough C. correction D. conceal A. inventor B. buy C. break the record D. choir A. March B. usual C. no good D. robot A. see a film B. armament C. by bike D. gray A. film B. critic C. nickname D. cloakroom A. poacher B. pilot C. on foot D. lazy A. infant B. dinosaur C. meanwhile D. hierarchy A. group B. above C. any D. efficiency A. close B. come to school C. swimming pool D. explode