People have smoked cigarettes for a long time now．The tobacco which is used to make cigarettes was first grown in what is now part of the United States．Christopher Columbus, who discovered America, saw the Indians smoking．Soon the dried leaves were transported to Europe．In the late 1800s, the Turks made cigarettes popular．
Cigarette smoke contains at least two harmful substances, tar and nicotine．Tar, which forms as the tobacco burns, damages the lungs and therefore affects breathing．Nicotine, which is found in the leaves, causes the heart to beat faster and increases the breathing rate．Nicotine in large can kill a person by stopping a person's breathing muscles．Smokers usually take in small amounts that the body can quickly break down．
Nicotine can make new smokers feel dizzy(头晕)or sick to their stomachs．The heart rate for young smokers increases 2 to 3 beats per minute．Nicotine also lowers skin temperature and reduces blood flow in the legs and feet．It plays an important role in increasing smokers' risk of heart disease and stroke．
Smoking cigarettes is dangerous．Cigarette smoking was the cause of lung cancer and several other deadly diseases．
(1)
What is the main purpose of the first paragraph?
[ ]
A．
To tell us the bad effects caused by smoking cigarettes．
B．
To introduce the history of smoking．
C．
To let us know what the cigarettes are made from．
D．
To tell the readers that Columbus found the Indians smoking．
(2)
________ doesn't make one's heart beat as usual．
[ ]
A．
Tar
B．
Nicotine
C．
Lung disease
D．
Leaves
(3)
The following effects are caused by Nicotine EXCEPT that ________．
[ ]
A．
It can make new smokers feel dizzy or sick to their stomachs
B．
It lowers skin temperature
C．
It causes the heart to beat less fast
D．
Nicotine will probably kill a person if a smoker takes in too much of it．
More than seven hundred years ago, the Prince of Wales had a very big and brave dog called Gelert．One day the Prince wanted to go hunt-ing with his men．He told his dog to stay at home and look after his baby son．The baby was in a wooden cradle, which was like a small bed．When the Prince came back from hunt-ing, Gelert ran out to meet his master．He wagged his tail and jumped up to put his paws on the Prince's chest．Then the Prince saw the blood on Gelert's jaws and head．
"What have you done?" the Prince said．He rushed into his house and looked for his baby son．The cradle was lying on its side on the floor．The clothes were torn and there was blood on them．
"So you have killed my son?" the Prince said angrily．"You unfaithful dog!" He took out his sword and killed the dog．Just as Gelert was dying, he managed to bark．Then the Prince heard a baby call to the dog．
The Prince ran out of the house and saw his son lying on the ground unhurt．Near him was a dead wolf．Then the Prince knew that Gelert had defended the baby and killed the wolf．
The Prince ran back into the house but he was too late．Gelert was dead．The Prince was very sad indeed．Tears ran down his face when he realized 'he had killed his faith-ful friend．The Prince carried the body of his brave dog to the top of a mountain and buried him there．After this, the Prince never smiled again．Every morning at dawn, he walked up the mountain and stood by the dog's grave for a few minutes．
If you go to Mount Snowdon in Wales, people will show you where Gelert is buried．There is a sign by his grave．It reminds peo-ple of a brave and faithful dog．
(1)
Gelert was the dog of the Prince of _________．
[ ]
A．
Scotland
B．
England
C．
Ireland
D．
Wales
(2)
The Prince told the dog to _________ when he was leaving．
[ ]
A．
watch the door
B．
take care of his baby at home
C．
welcome his friends
D．
stop the strangers
(3)
The dog was very _________ when his master came back from hunting．
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