下列说法正确的是 A．将钠投入硫酸铜溶液中只有紫红色固体析出 B．过氧化钠投入硫

阅读理解。

     It was a hot Sunday afternoon and the two of us were heading for the capital city. Suddenly my son

gave a shout of pain. He had somehow managed to tangle up (围绕) his small body in his seat belt. I

immediately pulled off the road.

     I could have tried to stop a car, but they were driving by so fast. At that moment, I would have cut

the belt if I had something to cut it with. Then I thought that I could retract (缩回) little further in order

that it might work. But if that failed, my son's little stomach would be squeezed even tighter.

     Just then a man appeared. He wore a white shirt and trousers that I'd seen on Costa Rican cowboys

and his clothes so dirty that I thought he might be a beggar or worse.

     Yet when the stranger reached us, he asked me if I needed help. I pointed to my son and he took a

look. He then bent down beside my son, tracing the path of the smooth seat belt with with his rough fingers. After a long moment, he asked my son to bend sideways and a little bit forward. He then put his hands

on the belt, controlled it in a way that I still don't understand now, and my son was free.

     I thanked him warmly. I also reached into my wallet and gave him a bill, although his calm face

suggested that he didn't care about a reward. He had found a new way to use his roping skills, particularly those he used when freeing animals. And I had experienced the kindness.

1. What happened to the author's son? 

A. He was unable to move in his seat belt.

B. He suddenly suffered from a stomachache.

C. He fell off his seat and hurt his stomach.

D. He saw something interesting on the journey.

2. From the passage, we know the cowboy __________.  

A. taught the author how to free her son      

B. was familiar with the author's son

C. refused to accept the money            

D. was good at roping.

3. What would be the best title for the passage? 

A. cowboy in Costa Rican.

B. A kind and quick roadside help.

C. A hard journey

D. A story of a cowboy

出入颈静脉孔的神经是（）。

A.迷走神经

B.舌下神经

C.舌咽神经

D.三叉神经

E.副神经

复发疝首选的术式是（）

A.Ferguson法

B.Bassini法

C.McVay法

D.疝成形术

E.疝囊高位结扎术

在合同法律适用领域，最早采用的灵活的开放性的连结点是（）

A.缔约地

B.履行地

C.意思自治原则

D.最密切联系原则

两机动船相遇，双方避让意图经声号统一后，避让行动能否改变？《内规》对避让船舶有何要求？