对钢结构的特点描述正确的是（）。 A.密闭性好 B.耐热性和耐火性较好 C.强度高、

读句子，根据汉语或首字母提示补全单词。

1. The policeman told that man to give a ________ (描述) of the accident.

2. W_______ is the third day of a week.

3. We are often told not to be ________ (紧张) in the examinations.

4. The weather in South China is d________ from that in North China.

5. That book is well ________ (值得) reading. You'd better read it.

模式植物细胞

儿童多动症治疗的首选药物为（）

A.利他林

B.可乐定

C.氟哌啶醇

D.特可林

E.氟伏沙明

被称为“环境友好使者”的草种是（）

A、野牛草

B、冰草

C、羊茅

D、狗牙根

哪些因素影响炉渣的粘度？