在碱性尿液中，能使尿液显红色的药物是
A. 硝苯地平
B. 亚甲蓝
C. 酚酞
D. 叶酸
E. 复合维生素B
有机磷中毒的机制是可使
A. 巯基酶失活
B. 细胞色素氧化酶失活
C. 胆碱酯酶失活
D. 二氢叶酸还原酶失活
E. 环化酶失活
More than one example ______ necessary to make the students understand this rule clearly．
A. should be
B. is
C. are
D. have been
In England, people put their ______ first.
A. given names
B. full names
C. family names
D. English names
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