在下列人造板材中，表观密度小、吸声绝热性能好，可作为吸声或绝热材料使用的是（）。 A

（1）从诗题《观书有感》可以看出，这首诗不是单纯的风景诗，诗人通过具体景物的描写，表达了关于_____的心得体会。

（2）读《观书有感》，理解下列解释有误的一项是（     ）

A．鉴：镜子 

B．渠：渠水 

C．如许：如此 

D．为：因为

（3）对本诗《观书有感》理解有误的一项是（     ）

A．这首诗通篇运用比喻，寓情于景。

B．全诗生动形象，富与哲理，是以理成诗的佳作。

C．诗中的景物优美、生动，表达了诗人对景物的喜爱之情。

D．诗人表达了自己的体会：只有努力学习，博览群书，不断补充新鲜知识，才能博大精深。

励磁变保护有（）。

A、励磁变差动保护；

B、励磁变速断保护；

C、励磁变过负荷保护；

D、励磁变后备保护。

骨性关节炎

秋天到了，为了让幼儿认识秋天，老师精心准备了一幅秋天的图画挂在墙上，指导幼儿观察画中的景物，这是一种有效的教育方法。

If you left your book on the table overnight, you would find the following morning that it was still exactly where 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 table-cloth 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.

In this passage, inertia means ().

A. a situation in which no action is taken

B. a situation in which no progress is made

C. the feeling of someone not wanting to move or do anything

D. the force making an object stay at rest or continue moving