For years , many people would not believe that smoke could attack so many parts of the body in so many ways . Study shows , however , that tobacco isn’t one single thing .  At least 60% of it is gas—20 different kinds of gas . And one of these is the deadly carbon monoxide (CO) （一氧化碳）.
In factories , the amount of this gas in the air is measured , and it must be kept under fixed , safe level . But there is 640 times this safe amount in cigarette smoke .
Oxygen is carried through your body by the red blood cells . But this poison gas , CO, will get to the blood cells before the oxygen can . So , if you smoke your blood carries five to ten times more of this deadly gas than is normal . To make up for this , your body must make more red cells .
The oxygen in your blood passes into your tissues（组织）. But here again CO makes trouble . It keeps the oxygen from passing into your tissues as fast as it should . Because of this , cigarette country is always about 8000 feet above sea level . Someone who smokes and lives at sea level gets as little oxygen as a nonsmoker at an altitude（高度）of nearly two miles .This happens to everyone who smokes , no matter how old or how young . Anyone who competes in sports can tell you that those who smoke run out of breath more quickly than those who do not .
1．The gas amount in cigarette smoke is______________.
A．640 times higher than the gas safe levels in factories
B．640 times lower than the gas safe levels in factories
C．640 times as much as that in factories
D．as dangerous as that in factories
2．If you smoke , ______________ .
A．your blood carries more oxygen than is normal
B．your blood carries much more CO than is normal
C．you can have five to ten times of blood than usual
D．your blood will be poisonous
3．Those who smoke______________.
A．all live at sea level
B．don’t live at an altitude of two miles
C．breathe as much oxygen as non-smokers
D．only get the same amount of oxygen at the sea level as non-smokers at an altitude of nearly 2 miles
4．Smokers are______________.
A．easily hurt              B．easily excited      C．easily tired         D．healthy

For years , many people would not believe that smoke could attack so many parts of the body in so many ways . Study shows , however , that tobacco isn’t one single thing .  At least 60% of it is gas—20 different kinds of gas . And one of these is the deadly carbon monoxide (CO) （一氧化碳）.

In factories , the amount of this gas in the air is measured , and it must be kept under fixed , safe level . But there is 640 times this safe amount in cigarette smoke .

Oxygen is carried through your body by the red blood cells . But this poison gas , CO, will get to the blood cells before the oxygen can . So , if you smoke your blood carries five to ten times more of this deadly gas than is normal . To make up for this , your body must make more red cells .

The oxygen in your blood passes into your tissues（组织）. But here again CO makes trouble . It keeps the oxygen from passing into your tissues as fast as it should . Because of this , cigarette country is always about 8000 feet above sea level . Someone who smokes and lives at sea level gets as little oxygen as a nonsmoker at an altitude（高度）of nearly two miles .This happens to everyone who smokes , no matter how old or how young . Anyone who competes in sports can tell you that those who smoke run out of breath more quickly than those who do not .

1．The gas amount in cigarette smoke is______________.

A．640 times higher than the gas safe levels in factories

B．640 times lower than the gas safe levels in factories

C．640 times as much as that in factories

D．as dangerous as that in factories

2．If you smoke , ______________ .

A．your blood carries more oxygen than is normal

B．your blood carries much more CO than is normal

C．you can have five to ten times of blood than usual

D．your blood will be poisonous

3．Those who smoke______________.

A．all live at sea level

B．don’t live at an altitude of two miles

C．breathe as much oxygen as non-smokers

D．only get the same amount of oxygen at the sea level as non-smokers at an altitude of nearly 2 miles

4．Smokers are______________.

A．easily hurt                  B．easily excited      C．easily tired            D．healthy

The United States is a sports-loving nation. Sports in America take various forms: organized competitive struggles, athletic games, hunting and fishing. Most sports are seasonal, so that what is happening in sports depends upon the time of year.

Baseball is the most popular sport in the US. It is played throughout the spring and summer, and professional baseball teams play well into the fall.

Football is the most popular sport in the fall. The game originated as a college sport more than 75 years ago. It’s not the same as European football or soccer. In American football there are 11 players as well on each team, and they are dressed in padded uniforms and helmets because the game is rough and injuries are likely to occur. It is still played by almost every college and university in the country.

Basketball is the winner sport in American schools and colleges. Like football, basketball originated in the US, many Americans prefer it to football because it is played indoors throughout the winter and because it is a faster game. And the famous NBA games are considered the best of this game.

Other sports attracting a great many people include wrestling, boxing and horse racing. Although horse-racing fans call themselves sportsmen, the exactness of the term is questionable, as only the jockeys who ride the horses in the races can be considered athletes. The so-called sportsmen are the spectators, who do not come primarily to see the horses race, but to bet upon the outcome of each race. Gambling is the attraction of horse racing.

1.Baseball is so popular in America that some professional teams play it until ___________.

2.When playing football, American players are dressed in a special uniforms ___________.

3.Many Americans prefer basketball to football because______.

4.Horse-racing fans can’t be exactly considered as sportsmen because they ________.

5.The underlined word “jockeys” in the last paragraph refers to _______.

The United States is a sports-loving nation. Sports in America take various forms: organized competitive struggles, athletic games, hunting and fishing. Most sports are seasonal, so that what is happening in sports depends upon the time of year.

Baseball is the most popular sport in the US. It is played throughout the spring and summer, and professional baseball teams play well into the fall.

Football is the most popular sport in the fall. The game originated as a college sport more than 75 years ago. It’s not the same as European football or soccer. In American football there are 11 players as well on each team, and they are dressed in padded uniforms and helmets because the game is rough and injuries are likely to occur. It is still played by almost every college and university in the country.

Basketball is the winner sport in American schools and colleges. Like football, basketball originated in the US, many Americans prefer it to football because it is played indoors throughout the winter and because it is a faster game. And the famous NBA games are considered the best of this game.

Other sports attracting a great many people include wrestling, boxing and horse racing. Although horse-racing fans call themselves sportsmen, the exactness of the term is questionable, as only the jockeys who ride the horses in the races can be considered athletes. The so-called sportsmen are the spectators, who do not come primarily to see the horses race, but to bet upon the outcome of each race. Gambling is the attraction of horse racing.

Baseball is so popular in America that some professional teams play it until ___________.

A. spring            B. summer                 C. fall                D. winter

When playing football, American players are dressed in a special uniforms ___________.

A. to avoid unexpected injuries

B. to play it like European football

C. to make the game rough enough

D. to look like professional players

Many Americans prefer basketball to football because______.

A. NBA games are very popular           

B. it is originated in the US

C. it is much faster than football                

D. it is played indoors throughout winter

Horse-racing fans can’t be exactly considered as sportsmen because they ________.

A. mainly stand and watch the races

B. don’t ride horse in the races

C. are only interested in the results

D. don’t care who wins in the races

The underlined word “jockeys” in the last paragraph refers to _______.

A. the person who bets upon the the race

B. the person who cares about horse-racing

C. the rider who enjoys watching the race

D. the rider who competes in horse-racing

The United States is a sports-loving nation. Sports in America take various forms: organized competitive struggles, athletic games, hunting and fishing. Most sports are seasonal, so that what is happening in sports depends upon the time of year.
Baseball is the most popular sport in the US. It is played throughout the spring and summer, and professional baseball teams play well into the fall.
Football is the most popular sport in the fall. The game originated as a college sport more than 75 years ago. It’s not the same as European football or soccer. In American football there are 11 players as well on each team, and they are dressed in padded uniforms and helmets because the game is rough and injuries are likely to occur. It is still played by almost every college and university in the country.
Basketball is the winner sport in American schools and colleges. Like football, basketball originated in the US, many Americans prefer it to football because it is played indoors throughout the winter and because it is a faster game. And the famous NBA games are considered the best of this game.
Other sports attracting a great many people include wrestling, boxing and horse racing. Although horse-racing fans call themselves sportsmen, the exactness of the term is questionable, as only the jockeys who ride the horses in the races can be considered athletes. The so-called sportsmen are the spectators, who do not come primarily to see the horses race, but to bet upon the outcome of each race. Gambling is the attraction of horse racing.
【小题1】Baseball is so popular in America that some professional teams play it until ___________.