A. airplane B. annoying C. dedicate D. pollution A. be sure about B. discover C. historian D. stomach ache A. of course B. metal C. freely D. byproduct A. comedy B. bond C. comfortably D. be harmhul to A. get into B. which C. quietly D. suburban A. song B. write about C. slippery D. opening A. suspicious B. famous C. cruise D. glove A. director B. mirror C. basis D. directly A. travel B. exploit C. pity D. baker A. salesman B. against C. care about D. arrival