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

In the twentieth - century, people depend on unlimited energy to power their everyday lives. A wide range of energy-run devices and modern conveniences are taken for granted, and although it may seem that we will never be in danger of living without those conveniences, the fact is that many supplies of energy are dwindling rapidly. Scientists are constantly searching for new sources of power to keep modern society running. Whether future populations will continue to enjoy the benefits of abundant energy will depend on the success of this search.

Coal, oil, and natural gas supply modern civilization with most of its power. However, not only are supplies of these fuels limited, but they are a major source of pollution. If the energy demands of the future are to be met without seriously harming the environment, existing alternative energy sources must be improved or further explored and developed. These include nuclear, water, solar, wind, and geothermal power, as well as energy from new, nonpolluting types of fuels. Each of these alternatives, however, has advantages and disadvantages.

Nuclear power plants efficiently produce large amounts of electricity without polluting the atmosphere; however, they are costly to build and maintain, and they pose the daunting problem of what to do with nuclear waste. Hydroelectric power is inexpensive and environmentally safe, but impractical for communities located far from moving water. Harnessing energy from tides and waves has similar drawbacks. Solar power holds great promise for the future but methods of collecting and concentrating sunlight are as yet inefficient, as are methods of harnessing wind power.

Every source of energy has its disadvantages. One way to minimize them is to use less energy. Conservation efforts coupled with renewable energy resources, such as a combination of solar, water, wind, and geothermal energy and alternative fuels, such as alcohol and hydrogen, will ensure supplies of clean, affordable energy for humanity's future.

It can be inferred from the passage that _______ . 

A. Many alternative energy sources are environmentally hazardous 

B. solar and wind power are not promising for the future 

C. most alternative energy sources have proven to be impractical 

D. nuclear power solves one problem while creating others 

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.

A number of factors related to the voice reveal the personality of the speaker. The first is the broad area of communication, which includes imparting information by use of language, communicating with a group or an individual, and specialized communication through performance. A person conveys thoughts and ideas through choice of words, by a tone of voice that is pleasant or unpleasant, gentle or harsh, by the rhythm that is inherent within the language itself, and by speech rhythms that are flowing and regular or uneven and hesitant, and finally, by the pitch and melody of the utterance. When speaking before a group, a person's tone may indicate unsureness or fright, confidence or calm. At interpersonal levels, the tone may reflect ideas and feelings over and above the words chosen, or may belie them. Here the speaker's tone can consciously or unconsciously reflect intuitive sympathy or antipathy, lack of concern or interest, fatigue, anxiety, enthusiasm or excitement, all of which are usually discernible by the acute listener. Public performance is a manner of communication that is highly specialized with its own techniques for obtaining effects by voice and or gesture. The motivation derived from the text, and in the case of singing, the music, in combination with the performer's skills, personality, and ability   to   create  empathy   will  determine  the  success of artistic, political, or pedagogic communication.

Second, the voice gives psychological clues to a person's self-image, perception of others, and emotional health. Self-image can be indicated by a tone of voice that is confident, pretentious, shy, aggressive, outgoing, or exuberant, to name only a few personality traits. Also the sound may give a clue to the facade or mask of that person, for example, a shy person hiding behind an overconfident front. How a speaker perceives the listener's receptiveness, interest, or sympathy in any given conversation can drastically alter the tone of presentation, by encouraging or discouraging the speaker. Emotional health is evidenced in the voice by free and melodic sounds of the happy, by constricted and harsh sound of the angry, and by dull and lethargic qualities of the depressed

Why does the author mention "artistic, political, or pedagogic communication" in line 13?

A. As examples of basic styles of communication                  

B. As examples of public performance

C. To introduce the idea of self-image                           

D. To contrast them to singing

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions

Not until I got on the taxi to the airport that I realized I had left my passport at home

A. that I realized            

B. that I had left             

C. at home           

D. got on