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问题 单项选择题

学龄前儿童不宜用( )。

A．林可霉素类

B．四环素类

C．大环内酯类

D．青霉素类

E．头孢菌素类

答案

参考答案：B

解析：四环素和土霉素是抗生素类药，能治疗由许多种细菌引起的疾病，所以应用广泛。但学龄前儿童过多应用会使白牙“镶上”灰黄色“外衣”，故学龄前儿童不宜服用。

填空题

B Egyptian Villages 埃及村落

Most of the inhabitants live in mud-brick homes, their (1)  walls insulating against the afternoon heat. Flat roofs, exposed (2)  the northern evening breezes, serve as cool sleeping (3)  as well as storage areas. Villagers plaster the outer walls (4)  often trim them in blue, a color they believe (5)  off the evil eye. As a man becomes richer, (6)  can add a second story to his house perhaps (7)  his married son. Those villagers who have made the (8)  to Mecca paint the legend of their trip on (9)  outer walls of their homes. Such hajj houses, along (10)  the mosques, are the most distinguished buildings in a (11)

Some villagers build ornate pigeon coops close to their (12) , using the birds as food and their droppings to (13)  crops. Many houses still have dirt floors and lack (14)  or running water; women with jars balanced on their (15)  make the trek to the community well, and children donkeys haul the (16)  liquid in jerry cans.

All (17)  said, government sponsored building programs have also brought newer (18)  residences and utilities to some villages, particularly those outside (19)  Nile Valley in the Oases and the Red Sea (20)  areas.

10.（）
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填空题

移动通信的发展方向是从（）通信到数字通信，从窄带系统到（）系统，从话音业务到（）业务进行的。
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