[单项选择]Finger-prints have often been used as a method of solving criminal case because it ______.
A. is complicated but reliable
B. is simple and not expensive
C. is expensive but easy to do
D. can bring a lot of money

[单项选择]Finger-prints have often been used as a method of solving criminal case because it ______.
A. is complicated but reliable
B. is simple and not expensive
C. is expensive but easy to do
D. can bring a lot of money

[单项选择]Discards have been used by the Garbage Project to study ______.
A. the proportion of materials which break down within landfills
B. how much people eat and drink in their daily lives
C. the fluids that leak out of MSW landfills
D. how to compose the landfill wasters

[单项选择]

Pigeons have been used as messengers for 500 years, because of their special ability to find home. The mystery of the homing pigeon is on how it navigates and how it finds home. We now know that there are two ways that pigeons tell directions. First, they use the sun. Just getting rough directions from the sun is easy. However, getting accurate directions from the sun takes more care. To tell direction accurately from the sun, one needs to know the exact time.
All plants and animals seem to have built-in clocks. Usually these biological clocks are not quite exact in measuring time. However, they work pretty well, because they are “reset” every day, maybe when the sun gets up.
Do pigeons use their biological clocks to help them find direction from the sun We can experiment to find out. We can keep pigeons in a room lighted only by lamps. And we can time the lighting to make their artificial “days” start at some different time from the real
A. to send letters
B. to find home
C. to carry food for men
D. to lead the way for people

[单项选择]Pigeons have been used as messengers because ______.
A. they have a built-in compass
B. they can cover 500 miles in a single day
C. they have special ability to tell directions
D. they can find their way home

[单项选择]I have been out very often lately, and so would rather ______ at home this week.
A. be stayed
B. to stay
C. staying
D. stay

[单项选择]Foreigners often have either specific notions of ______ they think the British are like or, in desperation, wish for a unified picture of national character.
A. which
B. that
C. as
D. what

[单项选择]In this factory, suggestions often have to wait for months before they are fully ______.
A. admitted
B. acknowledged
C. absorbed
D. considered

[单项选择]In this factory, suggestions often have to wait fur months before they are fully ______ .
A. admitted
B. acknowledged
C. absorbed
D. considered

[单项选择]Very important people don't often have much free time as their work ______ all their time.
A. takes over
B. takes away
C. takes in
D. takes up

[单项选择]The technique of frying food has been used since antiquity----to prepare meats, fish, vegetables, and breads.
A. to have most cultures
B. that in most cultures
C. in cultures when
D. in most cultures

[单项选择]The windmill, which has been used for hundreds of years to pump water and grind grains, ______ redesigned to pro duce electricity.
A. it is now being
B. it now can
C. is now being
D. now being

[单项选择]—What do you often have for breakfast —Usually I have some milk and bread; ______ I have some noodles instead.
A. some times
B. at times
C. all the time
D. at one time

[单项选择]Conditions everywhere have been seriously worsened, ______ the postwar rise in prices.
A. as to
B. in relation to
C. owing to
D. with regard to