Exercise 6. Mark the letter A, B, C, or D to indicate the correct to each of the following questions.
51. A correction pen is used for ____ your writing mistakes.
A. cover B. covered C. covering D. to cover
52. It's no good ____ him the truth now.
A. not to tell B. tell C. telling D. to tell
53. It's important ____ too much about your failure.
A. not to worry B. not worry C. not worrying to D. don’t worry
54. Don’t forget ____ your homework before coming to class.
A. doing B. having done C. to be done D. to do
55. Did you remember ____ Mr. Green my message?
A. be given B. giving C. have given D. to give
56. 3-D printing ____ complex tools and components.
A. is used for produce B. is used to produce
C. uses for producing D. uses to produce
57. She was old enough ____ up her own mind.
A. made B. make C. making D. to make
58. My computer is used for ____ music and video.
A. having played B. play C. playing D. to play
59. My father uses a calculator to ____.
A. be calculated B. being calculated C. calculate D. calculating
