21. Although some societies are __undeveloped, their languages, from a linguist’s point of view, are very complex. A. technology B. technologically C. technological D. technologist 22. The ________ was a success; the patient will fully recover in a month’s time. A. operate B. operation C. operator D. operating 23. I like my work because I have the ________ to make my own decision. A. freed B. freedom C. freely D. free 24. That teacher is a(n) _______ one. His pupils like his sense of humor. A. amusing B. amused C. amusement D. self-amused 25. The road has just been ______ for better flows of traffic. A. width B. wide C. widely D. widened 26. She wants to look ______ in her wedding reception. A. natural B. naturally C. nature D. natured 27. Scientific progress supplies us with ______ such as washing machines, tractors,…. A. convenient B. conveniences C. inconvenience D. inconveniences 28. He was _________ in his final attempt. What a pity for him! A. successful B. successive C. unsuccessful D. success 29. You have to wear special clothes to work in the lab for the ________ of yourself. A. protective B. protector C. protection D. protectiveness 30. There are many interesting _________ events included in this book. A. historical B. historically C. historian D. history