He used to walk a long way to work. Now he______ to work.
A.still walks
B.no longer walks
C.walks
D.did not walk

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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 question.
All living cells in an animal's body require energy to power the various chemical processes going in inside them. This energy is ultimately supplied by the food that animals eat. These chemical processes are collectively referred to as metabolism, and one of the byproducts of metabolism is heat. Metabolic rates vary significantly between species. Warm-blooded animals (birds and mammals) have metabolic rates about five to ten times higher than those of similarly sized cold-blooded ones (reptiles, amphibians, and fishes). And it is precisely because birds and mammals have such high metabolic rates that they are able to keep their bodies warm.
The terms warm-blooded and cold-blooded are still in everyday use, but they are not entirely precise. Anyone who has handled a snake knows this because a snake’s body actually feels quite warm. But very little of the snake’s body heat originates internally, from its cells, most of it having been supplied from the outside, either by the sun or by a heat lamp. Instead of referring to reptiles as cold-blooded, they are best described as ectothermic, meaning “outside heat”. Similarly, birds and mammals are said to be endothermic, meaning “inside heat”.
There are advantages and disadvantages to each thermal strategy. Reptiles are usually sluggish first thing in the morning, their body temperatures having dropped during the cool of the night. Accordingly, they have to bask in the sun to raise their body temperatures, but once they have warmed up sufficiently, they can go about their business. By altering between the sun when they are too cool, and the shade when they are too warm, many reptiles are able to maintain their body temperatures at optimum levels of about 95°F or more. Endotherms, on the other hand, maintain temperatures of about 98°F all the time, so they are always ready for action.
I used to keep a crocodile. He had very sharp teeth, and I had to be careful how I handled him during the daytime, when he was warm. But I could do whatever I wanted at night, when he was cold, without any fear of being bitten. The obvious disadvantage of being ectothermic is that the animal’s activity levels are dependent upon the environment. But its low metabolic rates mean that it requires far less food, which is an advantage. I used to feed the crocodile a tiny piece of liver once a week, while the family cat demanded three meals every day. We should therefore not think that reptiles are inferior to mammals and birds; they are just different.
Why does the author mention his pet in the last paragraph?
A.Because he wants to advise on how to handle pets safely.
B.Because he wants to say that keeping a reptile as pet is less expensive.
C.Because he wants to compare reptiles’ metabolic rates with those of mammals and birds.
D.Because he wants to illustrate that ectothermism has both advantages and disadvantages.

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 question.
All living cells in an animal's body require energy to power the various chemical processes going in inside them. This energy is ultimately supplied by the food that animals eat. These chemical processes are collectively referred to as metabolism, and one of the byproducts of metabolism is heat. Metabolic rates vary significantly between species. Warm-blooded animals (birds and mammals) have metabolic rates about five to ten times higher than those of similarly sized cold-blooded ones (reptiles, amphibians, and fishes). And it is precisely because birds and mammals have such high metabolic rates that they are able to keep their bodies warm.
The terms warm-blooded and cold-blooded are still in everyday use, but they are not entirely precise. Anyone who has handled a snake knows this because a snake’s body actually feels quite warm. But very little of the snake’s body heat originates internally, from its cells, most of it having been supplied from the outside, either by the sun or by a heat lamp. Instead of referring to reptiles as cold-blooded, they are best described as ectothermic, meaning “outside heat”. Similarly, birds and mammals are said to be endothermic, meaning “inside heat”.
There are advantages and disadvantages to each thermal strategy. Reptiles are usually sluggish first thing in the morning, their body temperatures having dropped during the cool of the night. Accordingly, they have to bask in the sun to raise their body temperatures, but once they have warmed up sufficiently, they can go about their business. By altering between the sun when they are too cool, and the shade when they are too warm, many reptiles are able to maintain their body temperatures at optimum levels of about 95°F or more. Endotherms, on the other hand, maintain temperatures of about 98°F all the time, so they are always ready for action.
I used to keep a crocodile. He had very sharp teeth, and I had to be careful how I handled him during the daytime, when he was warm. But I could do whatever I wanted at night, when he was cold, without any fear of being bitten. The obvious disadvantage of being ectothermic is that the animal’s activity levels are dependent upon the environment. But its low metabolic rates mean that it requires far less food, which is an advantage. I used to feed the crocodile a tiny piece of liver once a week, while the family cat demanded three meals every day. We should therefore not think that reptiles are inferior to mammals and birds; they are just different.
What is the best title of the passage?
A.Birds and Mammals            
B.Endotherms and Ectotherms
C.Advantages of Entothermism  
D.Common Misconceptions about Reptiles

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.
            Many ants forage across the countryside in large numbers and undertake mass migrations; these activities proceed because one ant lays a trail on the ground for the others to follow. As a worker ant returns home after finding a source of food, it marks the route by intermittently touching its stinger on the ground and depositing a tiny amount of trail pheromone-a mixture of chemicals that delivers diverse messages as the context changes. These trails incorporate no directional information and may be followed by other ants in either direction.
            Unlike some other messages, such as the one arising from a dead ant, a food trail has to be kept secret from members of other species. It is not surprising then that ant species use a wide variety of compounds as trail pheromones. Ants can be extremely sensitive to these signals. Investigators working with the trail pheromone of the leafcutter ant Attatexana calculated that one milligram of this substance would suffice to lead a column of ants three times around Earth.
            The vapor of the evaporating pheromone over the trail guides an ant along the way, and the ant detects this signal with receptors in its antennae. A trail pheromone will evaporate to furnish the highest concentration of vapor right over the trail, in what is called a vapor space. In following the trail, the ant moves to the right and left, oscillating from side to side across the line of the trail itself, bringing first one and then the other antenna onto the vapor space. In following the trail, the ant moves to the right and left, oscillating from side to side across the line of the trail itself, bringing first one and then the other antenna into the vapor space. As the ant moves to the right, its left antenna arrives in the vapor space.The signal it receives causes it to swing to the left, and the ant then pursues this new course until its right antenna reaches the vapor space. It then swings back to the right, and so weaves back and forth down the trail.
According to the passage, how are ants guided by trail pheromones?
A.They avoid the vapor spaces by moving in a straight line.
B.They concentrate on the smell of food.
C.They follow an ant which is familiar with the trail.
D.They sense the vapor through their antennae.