下述卡环常规设计中具有固定松动牙作用的是（） A.连续杆式卡环 B.联合卡环 C.环

If you left your book on the table overnight, you would find the following morning that it was still exactly when you had left it, provided nobody had moved it. If a ball is made to roll on a very smooth surface, it will roll a long distance unless something stops it or changes its direction. This tendency of an object to remain at rest unless something moves it and to continue moving unless something stops it is known as the Law of Inertia.
The following examples show the truth of this law.

• (a) Put a table-cloth on a table and arrange a pile of books on it. Hold one edge of the tablecloth and pull it quickly. The table-cloth will come off, leaving the pile of books undisturbed.
• (b) Place a small piece of cardboard on an open jar and place a coin on it directly over its mouth. Use one finger to flick the piece of cardboard away. You will notice that the coin drops into the jar.
• (c) Sitting in a car which starts suddenly, you feel you are jerked backwards. In fact, you are not jerked backwards. Your lower half, which is in contact with the cushion, is forced to move forward with the car, and the upper part of your body, which remained at rest, is left behind.

This passage, on the whole, is developed by ______.

A．time

B．space

C．process

D．example

金口义齿初戴时发现下牙弓明显后退其原因最可能是()

A．人工牙排列不当

B．确定水平颌位关系时下颌前伸

C．架前后移动

D．病员下颌骨过后退

E．垂直距离过高

下列哪一选项不能成立( )

A．法律通过划定自由权利的界限，为普遍自由的实现提供前提

B．古罗马法学家乌尔比安在《学说汇纂》中指出：法“它来自于‘正义’。实际上(正如杰尔苏所巧妙定义的那样)法是善良和公正的艺术”

C．由于阶级的多样性和政治的复杂性，因而法律价值之间会发生一定的冲突

D．法律担负着实现资源最大限度地优化使用与配置的社会新使命

地龙与僵蚕具有的共同功效是（）

A.息风止痒

B.息风止痛

C.息风止痉

D.息风明目

E.息风平喘

患者女性，58岁，10天来咳嗽、发热38.5℃，自服感冒药不见好转，黄痰逐渐增多，30～50ml/d，偶尔有脓血痰。白细胞19×10⁹/L。胸片见右肺有大片模糊阴影，其中有一带液平面的薄壁空洞。门诊首先考虑（）

A.肺结核

B.中央型肺癌

C.支气管肺炎

D.支气管扩张

E.肺脓肿