31. There is no ______ for them to do that. A. need B. needs C. needless D. needing 32. The _____ development leads to our country’s prosperity. A. industry B. industries C. industrial D. industrialize 33. Farmers ______ their land to make it _______. A. fertilize / product B. fertilizer / productive C. fertilize / production D. fertilize /productive 34. Many communities are burning garbage and other biological waste products to produce ______. A. electric B. electricity C. electrician D. electrify 35. _______wildlife needs the cooperation of the public. A. safe B. safety C. safeguard D. safeguarding 36. Stress and tiredness often lead to lack of _______. A. concentrate B. concentration C. concentrated D. concentrator 37. Human being are the worst _______ on the earth. A. pollutes B. polluters C. pollutants D. pollutions 38. A combine harvest is very ______, it can cut and thresh rice at the same time. A. use B. useless C. useful D. usefulness 39. Mrs. Christine has been told by her doctor that she is _________, she cannot have a child of her own. A. childless B. childhood C. childish D. child 40. Are you _____ of the danger that you are facing? A. sense B. sensible C. senseless D. sensation 41. Thanks to my friends’ ________ remarks, my essay has been improved. A. construct B. construction C. constructive D. constructor 42. What is your _____ in life? A. aim B. aimless C. aimlessly D. aimlessness 43. The matter is under ______. A. investigate B. investigation C. investigatory D. investigative 44. The president traveled under the ______ of many soldiers. A. protect B. protective C. protection D. protector 45. The US made a _____ declaration of war to Iraq. A. formal B. formality C. formalize D. formalism