[填空题]Scientists think that laser (be)（）one of the most useful tools today.

[填空题]Scientists think laser (be)（）one of the most useful tools today.（）

[填空题]Scientists think laser (be) ______ one of the most useful tools today.

[简答题]Some people think that scientists make the most important contributions to society. Other people think that the contributions of artists are the most important. Which position do you agree with Give specific reasons and examples to support your answer.

[单项选择]Astronomers and scientists think that a black hole is a region of space ______ which matter has fallen and ______ which nothing can escape.
A. into; from
B. towards; towards
C. out of; from
D. through; through

[填空题]What do scientists think of dreams
Many scientists believe that dreams are （）.

[填空题]Scientists think that we should blame the virus of flu all on wild birds.

[填空题]Many scientists think the whale does not feed after it leaves the breeding ground until it reaches the Arctic again.

[单项选择]What did the 19th century scientists think about our brain
A. Different part of the brain had different effect.
B. Chemical changes stopped during our sleeping;
C. There was a storehouse in the brain.

[填空题]Scientists think the moralists’ warning is ______.

[单项选择]

One of the most famous scientists to study adaptations (适应能力) was Charles Darwin (达尔文). He was born in England in 1809. He wasn’t the best student in his school, but when he was 16, his father sent him to a medical school. Charles liked spending time outdoors observing (观察) nature more than attending medical classes. He dropped out without graduating.
Next, Charles’ father sent him to school to become a minister (牧师). This time he made it to graduation. But he didn’t want to do the work of a minister. His friends encouraged him to follow his interest in science.
After graduation, Charles was invited to sail on the Beagle as an unpaid scientist. He wasn’t the first choice, but he was the lucky one to go. The Beagle was to travel to South America and then around the world. The crew’s task was to make maps of the places they visited.
On December 27th, 1831, Charles Darwin sailed from England on the Beagle. The trip was planned to
A. twenty-three
B. twenty-two
C. forty-five
D. fifty