下列细菌中不需作血清学分型鉴定的是A．大肠埃希菌0157:H7 B．伤寒沙门菌 C．

从辩证法角度看，高速铁路在我国有着广阔的发展前景，这是因为

①它具有强大生命力和远大发展前途   

②新出现的事物，前途都是光明的

③符合我国实际，坚持了一切从实际出发   

④它是对旧的铁路模式的彻底改变

A．①

B．①②

C．①②③

D．①②③④

It was in 1949 _____ the People's Republic of China was founded. [ ]

A. when

B. that

C. in which

D. which

阅读理解。

     A young man named Charles Lyell had different ideas. He

wrote a book about them called Principles of Geology. The earth,

according to Lyell, was not only thousands of years old, it was

millions of years old. As to (关于) the common belief that changes

in the earth's surface happen suddenly because of a single

earthquake or flood, he said that this might happen once in a

while, but usually these changes took place very slowly. He

believed that the surface of the earth had been changing from the

beginning of time. The changes, he said, were caused by the long-

term action of the winds and seas, and by forces such as volcanoes

breaking out under the earth's surface. Once in a great while he

thought, a mountain might appear for the first time after an

earthquake. But usually mountains would rise slowly and steadily.

      Professor Henslow was interested in Lyell's ideas, but he did

not actually believe them. Charles Darwin could not make up his

mind about them. But they set him thinking along lines which would

later change the beliefs of thoughtful people all over the world.

       At Cambridge ,Charles Darwin studied just enough to pass the

examination, and received his college degree in 1831. During this

time, he had become more and more interested in geology. At the

end of the school year, he went to North Wales with one of his

teachers to examine the rock formations (构成)  and to search for

fossils (化石). Fossils are the remains of ancient living things.

They are usually found fixed in rocks in the earth's crust (地壳).

Fossils may be of animals, such as fish, insects, birds, or

humans. They may be of plants from tiny leaves to huge trees.

         When a living creatures dies,  it usually decays (腐烂) or is

eaten by animals. However, if it sinks into a riverbed or is quickly

covered by the blowing sands of a desert storm, the bones are kept

up in the earth. Over many years the soft inner parts of a bone

disappear, leaving the inside bellow. Water containing mineral

enters into the hollow. Slowly the mineral hardens and makes the

bone hard and heavy, like stone.

1. According to Charles Lyell, it is mainly _____ that theearth has been formed like today's shape.   

A. from the beginning of time

B. past some experiences of big flood

C. over a very long period of years

D. because of several big earthquakes

2.  Charles Lyell believed the fact that a mountain is formed _____. 

A. more by seas than by volcanoes

B. more slowly than suddenly

C. more by an earthquake than by winds

D. more quickly than steadily

3. Unlike Professor Henslow, Charles Darwin  ____  .     

A. never thought Lyell's ideas were right

B. did made up his mind not to accept Lyell's ideas

C. thought about what the world was then

D. thought over Lyell's ideas and developed them

4.The main purpose of Darwin's going to North Wales was to ____.

A. make a study of fossils

B. appreciate the rock information

C. do research work into dead animals

D. look for plants from tiny leaves to huge trees

金钗石斛的性状特征有

A．扁圆柱形

B．表面金黄色或微带绿色

C．断面呈纤维性

D．气微，味苦

E．断面有多数散在的筋脉点

DEM6型轻便风向风速表，在观测风向时，必须待风杯转动约（）后，才能按下风速按钮。

A、1分钟

B、半分钟

C、1分半钟

D、2分钟