Read the passage, then choose the one best answer
In the last 100 years, technology has completely changed the way we live. At the touch of a button, we can look up almost anything we need to know on the Internet. We have electricity, aero planes. television, and we have ever been to the moon. So what sort of inventions will there be in the 21st century? In­deed. is there anything important still left to invent?
It seems that there is. Scientists all over the world are looking into Nan technology with a great deal of interest. This is the science of building small machines - and when we say small, we mean very small. To give you an idea of the size scientists are talking about, these machines would be about a million billion times smaller than the smallest bit of dust.
Nan technology will bring about enormous changes. Doctors, for example, will he able to cure any illness. The environment will be improved because it will be possible to take the polluted air we breathe and make it clean again. But perhaps the most exciting thought of all is that we won't have to wait a thousand years for Nan technology - many people believe there is a good chance it will come in our lifetime.
Which change will Nan technology not bring about?




A.Fatal diseases will be cured.
B.The air will be cleaner.
C.The pollution will be reduced.
D.The rare animals will be protected.

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Read the passage carefully, then choose the best answer for each question.
THE MEANING OF DREAMS
Did you have any interesting dreams last night?
Our dreams come from a part of the brain that contains our thoughts and memories. A person can have up to six dreams a night, and each dream usually lasts from 10 to 40 minutes. Everyone dreams, but not everyone remembers their dreams. Most people dream in color, usually with sound. And we usually dream about ourselves and the people we know.
Why Do We Dream?
Alan Siegel is a scientist who studies dreams. "Dreams help us get in touch with our deeper feelings,” he says. "They can tell us a lot about ourselves, and can help us figure out problems.” Another scientist, Robert Stickgold, thinks dreams come from our memories. He believes we dream to remember, because memories are useful to the brain. Stickgold says the purpose of dreaming through these memories is to help us learn from the past.
Here are a few types of dreams and what people think they mean.
Dream 1: You Meet Someone While in Your Pajamas
Sometimes people dream that they meet someone they know while wearing their underwear (or nothing at all!). This dream may be the result of an embarrassing event in your life. Some people think we dream about embarrassing situations if our brains are trying to deal with an event in our own lives.
Dream 2: You're Flying
If you dream about flying, you are probably quite happy. This is a good period in your life. You may feel that other people see you as a leader.
Dream 3: You Didn't Study for a Test
This probably means you are worried about an important event coming in your life. If you're not prepared for the event, your dream may be telling you, "It's time to get to work!"
If someone says, “The concert is tomorrow, and I haven’t had time to practice!” which dream from the passage might they have?




A.Dream 1: You Meet Someone While in Your Pajamas
B.Dream 2: You're Flying
C.Dream 3: You Didn't Study for a Test
D.None of these things