In Science, a theory is a reasonable explanation of observed events that are related. A theory often involves an imaginary model that helps scientists picture the way an observed event could be produced. A good example of this is found in the kinetic molecular theory, in which gases are pictured as being made up of many small particles that are in constant motion.

   After a theory has been publicized, scientists design experiments to test the theory. If observations confirm the scientists’ predictions, the theory is supported. If observations do not confirm the predictions, the scientists must search further. There may be a fault in the experiment, or the theory may have to be revised or rejected.

   Science involves imagination and creative thinking as well as collecting information and performing experiments. Facts by themselves arc not science. As the mathematician Jules Henri Poincare said: "Science is built with facts just as a house is built with bricks, but a collection of facts cannot be called science any more than a pile of bricks can be called a house."

   Most scientists start an investigation by finding out what other scientists have learned about a particular problem. After known facts have been gathered, the scientist comes to the part of the investigation that requires considerable imagination. Possible solutions to the problem are formulated. These possible solutions are called hypotheses. In a way, any hypothesis is a leap into the unknown. It extends the scientist's thinking beyond the known facts. The scientist plans experiments, performs calculations, and makes observations to test hypotheses. For without hypotheses, further investigation lacks purpose and direction. When hypotheses are confirmed, they are incorporated into theories.

In the fourth paragraph, the author implies that imagination is most important to scientists when they _______.

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• The story about college life in Amerian movies are not ...............

• The tone of the passage is that of .................

• What is the topic of the passage?

ZUNIA12

• Students who are not well – prepared to be young “adults” with all the responsibilities of life will need ______.

• Who is intended to benefit from the advice given in the article?

• The word “interfere” in paragraph 2 most nearly means ..........

• We sometimes think of writing as more real than speech because ..............

• The phrase ‘as well as’ in paragraph 4 is closest in meaning to ___.

• Why does the couple exchange garlands?

• Who were the subjects of the study?

• How many Americans are involved in telecommuting?

• The writer seems to imply that Europeans travel mostly for the reason that ...............

• The four boys of the Beatles .................

• The word "innovative" in line 1 could best be replaced by ...............

• It can be inferred from the passage that the eye ___.

• The "pounds" in the second paragraph are probably ...............

• It is stated in the passage that torches for lighting were made from ................

• In the second paragraph, the pronoun "them" refers to which of the following?

• What can the word invokes be best replaced by?

• According to the passage, all of the following contributed to the spread of English around the world EXCEPT .............