[单项选择]

Passage One 1
There is an English saying," Laughter is the best medicine." Until recently, few people took the saying seriously. Now, however, doctors have begun to look into laughter and the effects it bas on the human body. They have found that laughter really can improve people’s health.
Tests were carried out to study the effects of laughter on the body. People watched funny films while doctors checked their heart, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, the heart beating and breathing; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial.
Other tests have shown that laughter appears to be able to reduce the effect of pain on the body.. In one experiment doctors produced pain in groups of students who listened-to different radio programs. The group t
A. test
B. stop
C. reduce
D. increase

Passage One
There is an English saying," Laughter is the best medicine." Until recently, few people took the saying seriously. Now, however, doctors have begun to look into laughter and the effects it bas on the human body. They have found that laughter really can improve people’s health.
Tests were carried out to study the effects of laughter on the body. People watched funny films while doctors checked their heart, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, the heart beating and breathing; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial.
Other tests have shown that laughter appears to be able to reduce the effect of pain on the body.. In one experiment doctors produced pain in groups of students who listened-to different radio programs. The group tha
A. smiling does good to health
B. laughter can be tolerated
C. there is a way to reduce pain
D. laughter can work the muscles in the feet

Passage One 1
There is an English saying," Laughter is the best medicine." Until recently, few people took the saying seriously. Now, however, doctors have begun to look into laughter and the effects it bas on the human body. They have found that laughter really can improve people’s health.
Tests were carried out to study the effects of laughter on the body. People watched funny films while doctors checked their heart, blood pressure, breathing and muscles. It was found that laughter has similar effects to physical exercise. It increases blood pressure, the heart beating and breathing; it also works several groups of muscles in the face, the stomach, and even the feet. If laughter exercises the body, it must be beneficial.
Other tests have shown that laughter appears to be able to reduce the effect of pain on the body.. In one experiment doctors produced pain in groups of students who listened-to different radio programs. The group t
A. smiling does good to health
B. laughter can be tolerated
C. there is a way to reduce pain
D. laughter can work the muscles in the feet

Passage One
"A rolling stone gathers no moss (苔藓) ," but there is one living animal that does gather moss, the three-toed sloth (树獭) of South America. This slowest-moving member of the animal kingdom is so inactive that moss actually gathers on its body and turns it green strange as it seems!
Most of the sloth’s life is spent motionless, hanging upside down from a limb. And that is the way its hair grows. Long and coarse, the strands (串) from receptacles (花托) for the damp jungle algae (水藻) that turn the brown fur a mossy green. Actually this moss helps the animal survive because it serves as a per- fect camouflage against the leaf trees and hides the sloth from the jungle’s swift-moving hunters. The sloth would have little chance of survival on the ground. With long, curved claws hooked over the limb of a leafy tree, it spends the long hot hours during the day drowsing and eating. Inch by inch, it strips the leafy limbs bare and crawls
A. The sloth has only three toes
B. The sloth lives in the damp jungle of South America
C. The sloth usually tries to find a new spot for food at night
D. The sloth will never fight with other animals