56. Some of the most important breakthroughs in engineering should be _________ to mathematical researches.

　　A. contributed B. summed up

　　C. attributed D. delivered

　　57. Too much _________ to X-rays can cause skin burns, cancer or other damage to the body.

　　A. disclosure B. exhibition

　　C. contact D. exposure

　　58. The British Parliament is _________ of the House of Commons and the House of Lords.

　　A. composed B. consisted

　　C. made D. combined

　　59. Just as your supervisor advised, you ought to devote your time and energy to something _________ researching into.

　　A. valuable B. precious

　　C. worth D. worthy

　　60. Please don’t be _________ by his bad manners since he is merely trying to attract attention.

　　A. irritated B. distorted

　　C. disregarded D. intervened

　　61. The remarkable _________ of life on the Galapagos Islands inspired Charles Darwin to establish his theory of evolution.

　　A. classification B. diversity

　　C. density D. difference

　　62. The English language contains a(n) _________ of words which are comparatively seldom used in everyday conversation.

　　A. attitude B. altitude

　　C. multitude D. latitude

　　63. While typing, Helen has a habit of stopping __________ to give her long and flowing hair a smooth.

　　A. consistently B. instantly

　　C. eventually D. occasionally

　　64. Between 1897 and 1919, at least 29 movies _________, in which artificial beings of various kinds were portrayed.

　　A. had produced B. has been produced

　　C. would have produced D. had been produced

　　65. Hydrogen is the fundamental element of the universe _________ it provides the building blocks from which the other elements are produced.

　　A. so that B. but that

　　C. in that D. provided that