四环素类药物与铋剂、铁剂合用时影响吸收、降低其抗菌效果是因
A．生成混合物
B．生成化合物
C．生成单体
D．生成复合物
E．生成配位化合物
参考答案：E
—______ 42, Dmitry Medvedev becomes the youngest president of modern Russia.
—I know he ever became very ______ his students at university. [ ]
A. At the age of; popular with
B. At the age; popular
C. In the age of; popular for
D. In the age; popular with
请对对子。
（1）上联：滚滚波涛蕴宝藏
下联：________________________
（2）上联：________________________
下联：海洋乃人类未来粮仓
