The worry about salt is that it may…(1) high blood pressure. Chemically, salt …(2) of sodium and chloride ions, both of…(3) are common in the human…(4) and are important for many physiological and biochemical …(5). We not only need salt, we are salt, but too…(6) may still be bad for us. Although the idea of a…(7) between salt and high blood pressure…(8) back to 2000 BC, there is still no scientific…(9) as to whether this is so or not. One reason for this…(10) to agree is that individual salt intake…(11) enormously from day to day, and so reliable measures of intake are hard to come…(12).
Those who believe that salt does…(13) to high blood pressure…(14) to the high incidence of high blood pressure in countries that eat a very…(15) diet. In Japan, for instance, where salted fish is an important part of diet, high blood pressure and…(16) complications are common,…(17) among some Amazonian and African tribes, which have a low intake of salt, they are almost…(18).
But…(19) there is this neat relation between salt intake and the incidence of high blood pressure between countries, it doesn't seem to apply…(20) those countries themselves. Studies, for instance, of couples who have a similar salt intake don't show any consistency in how often they develop high blood pressure.

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1. What is the distance between Hanoi and Sapa?

A. How far is it between Hanoi and Sapa?

B. How far is it from Hanoi and Sapa?

C. How far is it from Hanoi to Sapa?

D. How far it is from Hanoi to Sapa?

2. I won’t hang these old paintings in the living room.

A. These old paintings won’t be hung in the living room.

B. These old paintings won’t be hanged in the living room.

C. These old paintings will be hang in the living room.

D. These old paintings will be hung in the living room.

3. The distance from Ho Chi Minh city to Phu Quoc Island is about 300km.

A. It is about 300 km from Ho Chi Minh city to Phu Quoc Island.

B. It is about 300 km between Ho Chi Minh city and Phu Quoc Island.

C. It takes about 300 km from Ho Chi Minh city to Phu Quoc Island.

D. It is about 300 km from Ho Chi Minh city and Phu Quoc Island.

4. Despite knowing the answer, she refused to help him.

A. Although she know the answer, she refused to help him.

B. Although she knows the answer, she refused to help him.

C. Although she knew the answer, she refused to help him.

D. Although she knews the answer, she refused to help him.

5. Be careful or you’ll fall off your bicycle.

A. If you are not careful, you won’t fall off your bicycle.

B. If you are careful, you’ll fall off your bicycle.

C. If you not careful, you’ll fall off your bicycle.

D. If you are not careful, you’ll fall off your bicycle.

6. In spite of his suffering from a bad cold, William went to school.

A. Although William suffers from a bad cold, he went to school.

B. Although William suffered from a bad cold, he went to school.

C. William went to school although he is suffering from a bad cold.

D. William went to school; although he suffered from a bad cold.

7. These are our pictures.

A. These pictures are our.

B. These pictures are our picture.

C. These pictures are ours.

D. These picture are our.

8. The football match was postponed because it rained heavily.

A. So the football match was postponed, it rained heavily.

B. It rained heavily, so the football match was postponed.

C. The football match was postponed so it rained heavily.

D. Because it rained heavily, so the football match was postponed.

9. We shall discuss the matter in the afternoon.

A. The matter will be discussed in the afternoon.

B. The matter shall be discussed in the afternoon.

C. The matter will be discussed in the afternoon by us.

D. The matter won’t be discussed in the afternoon.

10. All the students in this school will use new textbooks.

A. New textbooks will be use by all the students in this school.

B. New textbooks will be used by all the student in this school.

C. New textbooks will be used by all the students in this school

D. All the students in this school will used new textbooks.

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

Forces other than damaging winds are also at work inside tornadoes. Sometimes, as the writhing, twisting funnel passes over a house, the walls and ceiling burst apart as if a bomb had gone off inside. This explosion is caused by the low air pressure at the center of a tornado.

The pressure at the center of a tornado is usually 13 pounds per square inch. However, inside the house, the air pressure is normal, about 15 pounds per square inch. The difference of 2 pounds per square inch between the inside and outside pressure may not seem like much. But suppose a tornado funnel passes over a small building that measures 20 by 10 by 10 feet. On each square inch of the building, there is 2 pounds of pressure from the inside that is not balanced by air pressure outside the building. On the ceiling, that adds up to an unbalanced pressure of 57, 600 pounds. The pressure on the four walls adds up to 172,800 pounds.

If windows are open in the building, some of the inside air will rush out through them. This will balance the pressure inside and outside the building. But if the windows are shut tightly, the enormous inside pressure may cause the building to burst.

Unfortunately, heavy rain and hail often occur in thunderstorms that later produce tornadoes. So people frequently shut all windows to protect their property. This may cause far worse damage later. For the same reason, tornado cellars must have an air vent. Otherwise, the cellar door might be blown out when a tornado passes over it.

According to the passage, what is the difference per square inch between the air pressure inside a building and the air pressure inside a tornado?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.

Forces other than damaging winds are also at work inside tornadoes. Sometimes, as the writhing, twisting funnel passes over a house, the walls and ceiling burst apart as if a bomb had gone off inside. This explosion is caused by the low air pressure at the center of a tornado.

The pressure at the center of a tornado is usually 13 pounds per square inch. However, inside the house, the air pressure is normal, about 15 pounds per square inch. The difference of 2 pounds per square inch between the inside and outside pressure may not seem like much. But suppose a tornado funnel passes over a small building that measures 20 by 10 by 10 feet. On each square inch of the building, there is 2 pounds of pressure from the inside that is not balanced by air pressure outside the building. On the ceiling, that adds up to an unbalanced pressure of 57, 600 pounds. The pressure on the four walls adds up to 172,800 pounds.

If windows are open in the building, some of the inside air will rush out through them. This will balance the pressure inside and outside the building. But if the windows are shut tightly, the enormous inside pressure may cause the building to burst.

Unfortunately, heavy rain and hail often occur in thunderstorms that later produce tornadoes. So people frequently shut all windows to protect their property. This may cause far worse damage later. For the same reason, tornado cellars must have an air vent. Otherwise, the cellar door might be blown out when a tornado passes over it

In line 16, the word "it" refers to ________

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions that follow.

  Under certain circumstances, the human body must cope with gases at greater-than-normal atmospheric pressure. For example, gas pressures increase rapidly during a drive made with scuba gear because the breathing equipment allows divers to stay underwater longer and dive deeper. The pressure exerted on the human body increases by 1 atmosphere for every 10 meters of depth in seawater, so that at 39 meters in seawater a diver is exposed to pressure of about 4 atmospheres. The pressure of the gases being breathed must equal the external pressure applied to the body, otherwise breathing is very difficult. Therefore all of the gases in the air breathed by a scuba diver at 40 meter are present at five times their usual pressure. Nitrogen, which composes 80 percent of the air we breathe, usually causes a balmy feeling of well-being at this pressure. At a depth of 5 atmospheres, nitrogen causes symptoms resembling alcohol intoxication, known as nitrogen narcosis. Nitrogen narcosis apparently results from a direct effect on the brain of the large amounts of nitrogen dissolved in the blood. Deep dives are less dangerous if helium is substituted for nitrogen, because under these pressures helium does not exert a similar narcotic effect.

  As a scuba diver descends, the pressure of nitrogen on the lungs increases. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues The reverse occurs when the diver surfaces, the nitrogen pressure in the lungs falls and the nitrogen diffuses from the tissues into the blood, and from the blood into the lungs. If the return to the surface is too rapid, nitrogen in the tissues and blood cannot diffuse out rapidly enough and nitrogen bubbles are formed. They can cause severe pains, particularly around the joints.

  Another complication may result if the breath is held during ascent. During ascent from a depth of 10 meters, the volume of air in the lungs will double because the air pressure at the surface is only half of what it was at 10 meters. This change in volume may cause the lungs to distend and even rupture. This condition is called air embolism.

  To avoid this event, a diver must ascend slowly, never at a rate exceeding the rise of the exhaled air bubbles, and must exhale during ascent.

What does the passage mainly discuss?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions that follow.

Under certain circumstances, the human body must cope with gases at greater-than-normal atmospheric pressure. For example, gas pressures increase rapidly during a drive made with scuba gear because the breathing equipment allows divers to stay underwater longer and dive deeper. The pressure exerted on the human body increases by 1 atmosphere for every 10 meters of depth in seawater, so that at 39 meters in seawater a diver is exposed to pressure of about 4 atmospheres. The pressure of the gases being breathed must equal the external pressure applied to the body, otherwise breathing is very difficult. Therefore all of the gases in the air breathed by a scuba diver at 40 meter are present at five times their usual pressure. Nitrogen, which composes 80 percent of the air we breathe, usually causes a balmy feeling of well-being at this pressure. At a depth of 5 atmospheres, nitrogen causes symptoms resembling alcohol intoxication, known as nitrogen narcosis. Nitrogen narcosis apparently results from a direct effect on the brain of the large amounts of nitrogen dissolved in the blood. Deep dives are less dangerous if helium is substituted for nitrogen, because under these pressures helium does not exert a similar narcotic effect.

As a scuba diver descends, the pressure of nitrogen on the lungs increases. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues. Nitrogen then diffuses from the lungs to the blood, and from the blood to body tissues The reverse occurs when the diver surfaces, the nitrogen pressure in the lungs falls and the nitrogen diffuses from the tissues into the blood, and from the blood into the lungs. If the return to the surface is too rapid, nitrogen in the tissues and blood cannot diffuse out rapidly enough and nitrogen bubbles are formed. They can cause severe pains, particularly around the joints.

Another complication may result if the breath is held during ascent. During ascent from a depth of 10 meters, the volume of air in the lungs will double because the air pressure at the surface is only half of what it was at 10 meters. This change in volume may cause the lungs to distend and even rupture. This condition is called air embolism.

To avoid this event, a diver must ascend slowly, never at a rate exceeding the rise of the exhaled air bubbles, and must exhale during ascent.

What does the passage mainly discuss?