b) Mark the letter A, B, c or D to indicate the word that differs from the other three in the position of primary stress in each of the following ques

b) Mark the letter A, B, c or D to indicate the word that differs from the other three in the position of primary stress in each of the following questions.
21. A. Celebration B. Contribution C. operation D. remarkable
22. A. recognise B. recollect C. recommend D. understand
23. A. Compose B. recent C. gentle D. stupid
24. A. publish B. rewrite C. study D. practise
25. A. exercise B. decorate C. extinguish D. advertise
26. A. pillow B. alert C. legal D. model
27. A. register B. regular C. request D. reference
28. A. dangerous B. Curious C. suspicious D. numerous
29. A. voluntary B. Compulsory C. necessary D. stationary
30. A. Comfortable B. remarkable C. teenager D. sensible
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