nding in many fields of study.  82  a secondary school course, a student should be interested enough in a subject to enjoy gaining knowledge for its own  83  . He should be prepared to  84  sacrifices to study his chosen  85  in depth. He should have an ambition to make some  86  contribution to man’s knowledge.

67. A) at                B) by              C) to               D) in

68. A) turns             B) ranges           C) moves            D) varies

69. A) prospect          B) place            C) control            D) favor

70. A) occupy           B) possess          C) involve            D) spare

71. A) maximum         B) medium          C) virtual            D) vast

72. A) But              B) As              C) While             D) For

73. A) natural           B) essential          C) functional   &n