A.distinctive feature
B.minimal pair
C.complementary pair
D.perfect pair
A、Teachers
B、students
C、Teachers and students together
A、Yes, you can
B、I'd like a pair of sports shoes
C、Sorry, I don't know
D、NO. It's unnecessary
Boxing for Fitness (健身)
When it comes to boxing, most people think of two strong athletes in a ring trying to destroy each other with their fists. _____(1) It is a sport that people can get a great exercise from.
Boxing for fitness is fast becoming a popular way to exercise. It is easy to understand when you consider all the benefits of the sport. You will gain increased speed, skill and strength. _____(2) You will learn the basic attack skills and how to combine them effectively.
So you may wonder how I got started in boxing. I was already at the gym quite often, doing weight training. _____(3)But I was still soft around the midsection (上腹部).After a conversation with my boss at lunch one day he suggested I come to a boxing class with him. He is a very fit man in his 40s._____(4)And he told me all I needed to bring was a bottle of water and a towel.
If I have learnt anything from the experience, it is not to be afraid to try something new. No matter what your skill or fitness level is, boxing is good for you. The reason is that this exercise can be modified to suit you. _____(5)
(1)._____.
A、I was getting stronger.B、Boxing is considered too cruel.C、You will learn the proper way to control your feetD、He offered to lend me a pair of boxing gloves.E、All in all, boxing for fitness is a great way to work out.F、However, boxing for fitness is something altogether different
(2)._____.
A、I was getting stronger.B、Boxing is considered too cruel.C、You will learn the proper way to control your feetD、He offered to lend me a pair of boxing gloves.E、All in all, boxing for fitness is a great way to work out.F、However, boxing for fitness is something altogether different
(3)._____.
A、I was getting stronger.B、Boxing is considered too cruel.C、You will learn the proper way to control your feetD、He offered to lend me a pair of boxing gloves.E、All in all, boxing for fitness is a great way to work out.F、However, boxing for fitness is something altogether different
(4)._____.
A、I was getting stronger.B、Boxing is considered too cruel.C、You will learn the proper way to control your feetD、He offered to lend me a pair of boxing gloves.E、All in all, boxing for fitness is a great way to work out.F、However, boxing for fitness is something altogether different
(5)._____.
A、I was getting stronger.B、Boxing is considered too cruel.C、You will learn the proper way to control your feetD、He offered to lend me a pair of boxing gloves.E、All in all, boxing for fitness is a great way to work out.F、However, boxing for fitness is something altogether different
century by the Italian naturalist Lazzaro Spallanzani.He caught some bats in a bell tower,blinded them,and released them outdoors.Four of these blind bats were recaptured after they had found their way back to the bell tower,and on examining heir stomachs‘ contents,Spallanzani found that
they had been able to capture and gorge themselves with flying insects.We know from experiments that bats easily find insects in the dark of night , even when the insects emit no sound that can be heard by human ears.A bat will catch hundreds of soft-bodied,silent-flying moths or gnats in a single hour.It will even detect and chase pebbles or cotton spitballs tossed into the air.
16.According to the author,the sonar system of bats is an example of the idea that.()
A.this is the age of technological triumphs
B.modern machines are inefficient
C.living mechanisms are often more efficient than man-made
machines
D.artificial imitations are always less efficient than living
mechanisms
17.The author suggests that the sonar system of bats ().
A.was at the height of its perfection 50 million years ago
B.is better than man-made sonar because it has had 50 million years to be refined
C.would have been discovered by man many years ago
D.is the same as it was 50 million years ago
18.The fact that“blind bats”will detect and chase cotton spitballs as well as insects is remarkable because.()
A.bats do not eat spitballs
B.cotton is harder to track
C.Spitballs make no sounds audible to human ears
D.there is purpose in the flight of insects
19.This passage was written to illustrate().
A.the deficiencies of man-made sonar
B.the dependence of man upon animals
C.that we are living in a machine age
D.that the sonar system of bats is remarkable
20.Which of the following is the main point of the passage?()
A.A bat will catch hundreds of gnats in a single hour
B.Here is a perfection in nature which sometimes cannot be matched by man‘s creative efforts
C.The phrase“blind as bat”is valid
D.director of NIH learned of the abuse
假定有个消费者每月花费固定数额的收入在下述成对商品上:
(1)玉米饼和拉丁舞;
(2)玉米饼和炸土豆片;
(3)电影票和用咖啡豆磨制的咖啡;
(4)乘公共汽车出行和乘地铁出行。
假如上述成对商品中一种商品的价格上涨,说明这对每种商品需求的影响。在各对中,哪些可能是互补品?哪些可能是替代品?
Suppose that a consumer spends a fixed amount of income per month on the following pairs of goods:
a. tortilla chips and salsa
b. tortilla chips and potato chips
c. movie tickets and gourmet coffee
d. travel by bus and travel by subway
If the price of one of the goods increases, explain the effect on the quantity demanded of each of the goods. In each pair, which are likely to be complements and which are likely to be substitutes?
The first spectalces were made for ()
A、any one who had an eye trouble
B、the far-sighted
C、the short-sighted
D、both the far-sighted and the short-sighted
The first real steps took place in France, in 1783.Two brothers, the Montgolfiers, made a very large “hot air balloon”.They knew that hot air rises.Why not fill a balloon with it?The balloon was made of cloth and paper.In September of that year,the King and Queen of France came to see the balloon.They watched it carry the very first air passengers into the sky.The passengers were a sheep and a chicken.We do not know how they felt about the trip.But we do know that the trip lasted eight minutes and that the animals landed safely.Two months later,two men did the same thing.They rose above Paris in a balloon of the same kind.Their trip lasted twenty-five minutes and they travelled about eight kilometers.
26.Leonardo da Vinci ______ .
A.said that man would fly in the sky one day
B.built a kind of machine which never flew
C.drew many beautiful pictures of birds
D.made designs for flying machine
27.Eight hundred years ago an Englishman ______ .
A.made a kind of flying machine
B.tried to fly with wings made of chicken feather
C.wanted to build a kind of balloon
D.tried to fly on a large bird
28.In fact,the Englishman who tried to fly ______ .
A.lost his life
B.flew only 8minutes
C.got badly wounded
D.succeeded in flying
29.The very first air passengers in the balloon were ______.
A.two animals
B.two Frenchmen
C.the King and the Queen
D.the Montgolfiers
30.When did two Frenchmen rise above Paris?______
A.In December 1783.
B.In September 1783.
C.In November 1783.
D.In the seventeenth century.