下列产品的使用不会对环境造成污染的是 　[ ] A．含磷洗衣粉 B．酒精

具有雌激素样作用的是（）

A.海棠果内酯

B.双香豆素

C.橙皮苷

D.大豆素

E.紫杉醇

B

When I was a boy, my father told me that he could do anything he wanted to. Dad said that he wanted to be the first to develop color prints in our city. And so he did.

When I was 16，Dad looked closely at the violin I played and announced that he want to make one. He read about violinmaking，and then became a violinmaker at the age of 43. He bought the tools and materials，opened a small store and set Mom up as the shopkeeper，while he worked at a local company. He retired from the company 17 years later and continued to make violins and other instruments.

Dad often guessed why the Stradivarius violins sound so beautiful. Some experts claimed that it was the unique varnish(油漆)that gave those instruments their beautiful sound. Dad argued that chemists could analyze the varnish—if that were the answer.

One of Dad’s friends asked him once which kind of wood was used to make violins. When Dad explained that the top was made of spruce(云杉)，his friend said that he had an old piece of spruce Dad might be interested in.

He worked for the next 12 months making a violin from the wood that his friend had given him. It proved to be a superior violin and it would become Dad’s masterpiece. He was convinced that the secret of the Stradivarius sound was in the wood itself.

Later，the instrument was stolen. Dad’s spirit was broken by the robbery, and he stopped making instruments. But he kept the music shop until he was 80 years old, selling guitars and violins.

My father has been gone for 14 years now. The violin has been missing for more than 25 years. Somewhere a musician is playing a late-20th-century violin with an excellent tone. The owner today may never understand why this ordinary-looking violin sounds so much like Stradivarius.    

45. The author mentions his father’s developing color prints____________.

A. to show that his father’s real interest was not in making violins

B. to prove that his father could do anything he wanted to

C. to give an example proving that his father was an inventor

D. to describe the real thing that made the author believe his father

46. What did the author's father think about Stradivarius violins?

A. The varnish was different from the others.

B. The way of making them was special.

C. The wood of the violins was special.

D. They could only be analyzed by chemists.

47. From the underlined sentence, we can learn that the author’s father________.

A. 1iked the violin very much

B. got crazy after this happened

C. 1ost interest in instruments

D. didn't want to become famous

48. We can infer from the last paragraph that the author __________ .

A. really hates the thief

B. misses his father a 1ot

C. really wants to play the violin

D. wonders who’s playing the violin now

关于眼球贯通伤的叙述错误是（）

A.眼球贯通伤指一物体通过角膜或巩膜进入眼内，穿过眼球，从另一侧巩膜传出的双穿孔伤

B.眼球贯通伤是眼球穿孔伤中预后最差的一种外伤

C.眼球贯通伤预后差的关键是后部出口无法手术关闭

D.此外伤应性玻璃体切割手术，其目的是切除经伤道的纤维增生膜

E.手术时机以伤后7～14天为宜

由上皮和间叶成分构成的恶性肿瘤（）。

A.癌

B.肉瘤

C.癌肉瘤

D. * * 状瘤

E.畸胎瘤

F1，F2两力对某一刚体作用效应相同的充要条件是（）。

A、F1，F2两力大小相等

B、F1，F2两力大小相等，方向相同，作用在同一条直线上

C、F1，F2两力大小相等，方向相同，且必须作用于同一点上

D、力矢F1与力矢F2相等