[单项选择]

Two main techniques have been used for training elephants, which we may call respectively the tough and the gentle. The former method simply consists of setting an elephant to work and beating him until he does what is expected of him. Apart from any moral considerations this is a stupid method of training, for it produces a resentful animal who at later stage may well turn into a man-killer. The gentle method requires more patience in the early stages, but produces a cheerful, good-tempered elephant who will give many years of loyal service.
The first essential in elephant training is it assigns to the animal a single mahout who will be entirely responsible for the job. Elephants like to have one master just as dogs do; and are capable of a considerable degree of personal auction. There are even stories of half trained elephant calves who have refused to feed and pained to death when by some unavoidable circum stance they have been deprived of their own trainer. Such ext
A. early financial returns
B. their willingness to obey their trainers
C. the avoidance of anxiety in the elephant
D. that elephants are difficult to keep

[单项选择]

Two main techniques have been used for training elephants, which we may call respectively the tough and the gentle. The former method simply consists of setting an elephant to work and beating him until he does what is expected of him. Apart from any moral considerations this is a stupid method of training, for it produces a resentful animal who at later stage may well turn into a man-killer. The gentle method requires more patience in the early stages, but produces a cheerful, good-tempered elephant who will give many years of loyal service.
The first essential in elephant training is it assigns to the animal a single mahout who will be entirely responsible for the job. Elephants like to have one master just as dogs do; and are capable of a considerable degree of personal auction. There are even stories of half trained elephant calves who have refused to feed and pained to death when by some unavoidable circum stance they have been deprived of their own trainer. Such ext
A. two techniques used for training elephants
B. the inhumane method used in training elephants
C. how to train the elephant
D. the bad relationship between human beings and elephants

[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]Specifically equipped planes have been used ______.


A. to spread chemicals over the forest near Moscow airport
B. to spread chemicals over the planes to dear the fog around them
C. to spread chemicals over the fog lo help create "windows" in the fog for planes to land and take off
D. to spread chemicals over the runway at Moscow airport

[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]The oil must have been used up, （　） the light went out.
A. because
B. for
C. since
D. as

[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