[单项选择]Why is it important to know the entire process before the trip
[A] It makes sure you have a unexpected trip.
[B] It makes sure you have an exciting trip.
[C] It makes sure you have a pleasant and safe trip.

[单项选择]
Why is it important to know the entire process before the trip [A] It makes sure you have a unexpected trip. [B] It makes sure you have an exciting trip. [C] It makes sure you have a pleasant and safe trip.

[填空题]The professor wanted to know why many of her students did not complete their work or ask for help. She (47) to do a research project. She got the (48) of the university ethics committee. Such groups consider moral and legal (49) in studies.
In the spring of 2002, she (50) to her own university under the name "Rebekah Nathan" and was (51) . She lived in student housing. She took five classes during her first term and two in the second semester. She did pretty well, although she got one C, a mark of (52) . She also played sports.
The professor says her year as a student changed the way she teaches. She gives less reading now. She asks questions (53) to get students to speak more. She offers help. And she says she is no longer (54) if a student falls asleep.
Other professors and research experts, however, criticize the experiment. They say she was (55) . They say she could

[单项选择]Do you know why different animals or pests have their special colors Colors in them seem to be used mainly to protect themselves.
Some birds like eating locusts(蝗虫), but birds cannot easily catch them. Why It is because locusts change their colors together with the change of the colors of crops. When crops are green, locusts look green. But as the harvest time comes, locusts change to the same brown color as crops have. Some other pests with different colors from plants are easily found and eaten by others. So they have to hide themselves for lives and appear only at night.
If you study the animal life, you’ll find the main use of coloring is to protect themselves. Bears, lions and other animals move quietly through forests. They cannot be easily seen by hunters. This is because they have the colors much like the trees.
Have you ever found an even more strange act A kind of fish in the sea can send out a kind of very black liquid(液体)when it faces danger. While the liq
A. are small animals
B. are easily found by birds
C. are dangerous to their enemies
D. change their colors to protect themselves

[填空题]The teacher didn’t know why her students were discussing（）(noise).

[单项选择]Does Mrs. Bell know why the bottle of whisky is in her bag

[单项选择]I don’t know why UFOs are never sighted over large cities by hordes of people. But it is consistent with the idea that there are no space vehicles from elsewhere in our skies. I suppose it is also consistent with the ideas that space vehicles from elsewhere avoid large cities. However, the primary argument against recent extraterrestrial visitation is the absence of evidence.
Take leprechauns. Suppose there are frequent reports of leprechauns. Because I myself am emotionally predisposed in favor of leprechauns, I would want to check the evidence especially carefully. Suppose I find that 500 picnickers independently saw a green blur in the forest. Terrific. But so what This is evidence only for a green blur. Maybe it was a fast hummingbird. Such cases are reliable but not particularly interesting.
Now suppose that someone reports: "I was walking through the forest and came upon a convention of 7000 leprechauns. We talked for a while and I was taken down into their hole in the
A. one should not believe anything uninteresting
B. one should not believe anything which doesn’t occur in big cities
C. one should not be too ready to believe things before checking the evidence
D. one should not expect anything strange to occur in the sky over the big cities