仓库通风有（）等方式。A.自然通风 B.机械自然通风 C.机械循环通风 D.制

下述关于固有口腔境界的描述，错误的是（）

A.前界为牙列

B.上界为腭

C.下界为舌下区

D.两侧为颊

E.后界为咽门

In this            conflict, about 20 common people were killed.  

A．gentle

B．violent

C．fundamental

D．harmful

根据下面的对话情景，在每个空白处填上一个适当的句子，使对话的意义连贯、完整。

A: Hello! 65772896.

B: Hello! This is Lucy. 1.                         ?

A: Yes. This is Alice speaking. 

B: 2.                        ?

A: I'll have nothing to do this evening. I've finished all my homework.

B: 3.                        ? I've got two tickets for the movie "Superman".

A: Sure, I'd love to. I want to see "Superman" very much. I've heard it's so exciting. 4.                       ! Then

    I would do everything I have always wanted to.

B: That's impossible. By the way, 5.                           ?

A: Let's meet at the No. 3 bus stop at 6 pm.

B: OK! See you then.

一个视图只反映长.宽.高中的一个要素的大小。

化学元素在岩石圈中存在的基本单元是（）

A．岩石

B．矿物

C．矿床

D．矿产