The author's primary purpose in writing this passage was to ______.
A. plead for the abolishment of uniforms
B. show that uniforms are not possible in a democratic society
C. discuss the pros and cons of wearing uniforms
D. convince the reader that uniforms have more disadvantages than advantages
引入芳环可使毒性增加的基团是
A. 磺酸基
B. 硝基
C. 卤素
D. 羟基
E. 巯基
This passage might be found in which of the following
A children's textbook.
B. An editorial in a newspaper.
C. A sociology textbook.
D. A political platform.
According to the passage, it was Dr. Lillehei that ______.
A. first developed applied bionics
B. was the first to operate on the heart of a patient
C. developed the artificial heart
D. used more sophisticated methods to do "open heart" surgery
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