A. scientists B. science C. scientific D. sciences
A. coming B. come C. comes D. came
A. arrival B. arrived C. arrives D. arriving
A. help B. helpful C. helping D. helps
A. width B. wide C. widen D. wided
A. care B. caring C. cared D. careful
A. invention B. invented C. invent D. inventing
A. am used to B. used to C. used D. was used to
A. fairly B. fair C. unfair D. faired
A. possible B. impossible C. possiblely D. inpossible
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