补偿收缩混凝土浇筑完成后，应及时对暴露在大气中的混凝土表面进行潮湿养护，养护期不得少

阅读理解

     If you see someone drowning, speed is very important. Once you get him out of the water, if he isn't

breathing, you have four minutes before his brain is completely destroyed.  Support his neck, tilt(使翘

起) his head back and press his chin (下巴) upwards.This stops the tongue blocking the airway in the

throat and is sometimes enough to get him breathing again. If that doesn't work, start mouth-to-mouth

breathing. Prees his nostrils (鼻孔) together with your fingers. Open your mouth and take a deep breath.  Blow into his lungs until his chest rises, then remove your mouth and watch his chest fall. Repeat

twelve times a minute. Keep doing until help arrives.

    To bring a child back to life, keep your lips around his mouth and nose and gently blow into his

mouth. Give the first four breaths as quickly as possible to fill the blood with oxygen. If, in spite of your

efforts, he starts tuming a blue-grey colour, and you can feel no pulse (脉搏) , then pressing is the last

chance of saving his life.

    With arms straight, rock forwards, pressing down on the lower half of the breastbone. Don't be too

hard or you may break a rib(肋骨). Check how effective you are seeing if his colour improves or his

pulse becomes independent to your chest pressing. If this happens, stopthe pressing. Otherwise continue

until rescue amves.

1. This passage is mainly about          .

A. how to save people out of the water

B. how to give first aid to people who are drowning

C. how to do mouth-to-mouth breathing

D. how to save a child from a nver

2. Once you get a drowning man out of the water, if he isn't breathing, you must first       .

A. get him breathing again

B. take him to the nearest hospital as soon as possible

C. find someone to help you

D. call the First Aid Centre

3. In the last paragraph, the underlined word "rescue" means       .

A. breath                    

B. help

C. doctor                    

D. pulse

4. If the drowning boy has no pulse,        .

A. pressing his chin upwards is enough to get him breathing

B. blowing air into his mouth is sure to save his life

C. pressing his nostrils together with your fingers can work

D. pressing is the last chance of saving his life

商品证券是证明持券人对其证券所代表的商品具有（）的凭证。

A．所有权或使用权 

B．租赁权或转让权 

C．收益权或处分权 

D．使用权或转让权

术后第3天患者体温达38.9℃，切口处皮肤触痛，有红肿，可能的原因是

A．吸收热

B．体液代谢紊乱

C．切口感染

D．脱水热

E．盆腔脓肿

用方差—协方差法计算VaR时，其基本假设之一是时间序列不相关。若某序列具有趋势特征，则真实VaR与采用方差—协方差法计算得到的VaR相比，( )。

A．较大

B．一样

C．较小

D．无法确定

学习迁移的种类。