Why is a special substance painted on the tree?

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• The process that occurs when heat is generated by a chemical reaction within a substance and continues to a point of ignition is known as （）.

  A . chemical ignition B . spontaneous combustion C . chemical combustion D . radiation ignitio

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• Which of the substances listed is satisfactorily removed from the fuel by a centrifugal oil purifier?（）

  A . Impurities B . Lube oil C . Gasoline D . Diesel fuel

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• Each cylinder is closed at the top by a （）, made of a special heat-resistant steel.

  A . cylinder liner B . coupling flange C . cylinder cover D . piston crow

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• Which area is designated a special area by Annex V to MARPOL 73/78? （）

  A . Gulf of Mexico B . Sargasso Sea C . Red Sea D . Great Lake

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• What is a“Special Warning”（）.

  A . An urgent message concerning a vessel in distress B . A weather advisory about unusual meteorological or oceanographic phenomena hazardous to vessels C . A broadcast disseminating an official government proclamation affecting shipping D . A radio navigational warning concerning a particularly hazardous condition affecting navigatio

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• The heat required to change a substance from a solid to a liquid while at its freezing temperature, is known as the latent heat of （）.

  A . fusion B . vaporization C . condensation D . sublimatio

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• A substance found in residual fuels which tends to cause exhaust valve corrosion and grooving, is（）

  A . carbon B . vanadium C . calcium D . hydroge

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• A special daymark is a（）.

  A . red-and-white octagon B . daymark with a yellow stripe on it C . green square D . yellow diamond

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• A vessel emitting harmful substances into the air or spilling oil into the sea is a（）.

  A . polluter B . emitter C . spiller D . oiler

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• A_______ is a planned activity that makes up a special event.

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• In his IDEAL statement, Taleeb says he feels special. Why does he feel special?

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• Light is a harmful substance.

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• Practical English is a special language used in the situations of practical work.

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• This chemical is made____a special formula.

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• Coral is a kind of small organism called limestone living within a skeleton made of a substance called polyps.

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• Eight-Treasure porridge is a special food on the day of ____.

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• Why does the author think it is wrong to believe that “the public speaker is a specially gifted individual” (Para. 4)?

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• 121.A vessel emitting harmful substances into the air or spilling oil into the sea is a( )。

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• If a substance is dissolved in water or heated, it may-______ a gas.

  A．give into B．give over C．give off D．give away

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• A．People should pay special attention to sub-health since it is a very dangerous state.

  B．Healthy lifestyle. and a balanced diet are quite useful for people to recover from sub-health. C．More than half of sub-healthy people are middle-aged or old people. D．People should eat more to become stronger in order to avoid sub-health.

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• What is a special feature of Wilkin's Hotel？

  A．It is normally very busy. B．It is close to the conference venue. C．It has an attractive view. D．It is near a tourist destination.

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• What is the reason that Mr. Baker made a special request？

  A．The rooms have already been booked solid. B．Mr. Baker"s company has overdue payments. C．The number of guests is not enough. D．Mr. Baker"s company has already received a discount before.

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• Many science reports discuss medical studies that test the effect of a new drug. Usually, a large number of people is divided into two groups. Each group takes a different substance. But no one knows which group is getting which substance. One group takes the medicine being tested. Another group takes what we call an inactive substance. Medical researchers call this substance a "placebo." The word "placebo" is Latin for "I shall please." Placebo pills(宽心丸)usually are made of sugar.

  Using placebos to test drugs sometimes has a surprising result. Researchers say people taking the placebo often report improvements in their health. This is known as "the placebo effect"--pain that is eased or stopped by an inactive substance. In such testing, the drug must perform. better than the placebo to prove that it is effective. Doctors have reported that the placebo effect can be used in treatment. For example, a doctor tells a patient that a new drug will stop the pain in his leg. The pill is only sugar. But the patient does not know that. He takes the pill and says his pain is gone. Scientists are beginning to discover some physical reasons for this reaction in some people. They are learning that much of what people believe to be true comes from what the brain expects is going to happen. If the brain believes a drug will ease pain, the brain may begin physical changes in the body that can cause the expected effect. A recent examination of studies on drugs for depression found that placebos eased the depression about as well as the active drugs. Other studies have explored the power of placebos. A study in Japan involved thirteen people who reacted to the poison ivy (常青藤)plant. Poison-ivy causes red itchy sores(伤痕)on some people who touch it. Each person was rubbed on one arm with a harmless leaf, but was told it was poison ivy. Each person was then touched on the other arm with poison ivy, but was told it was a harmless leaf. All thirteen people developed a reaction on the arm where the harmless leaf touched their skin. Only two reacted to the poison ivy leaves. Doctors and scientists worry that the use of placebos may not always be harmless. They say people can become victims of false doctors and others who use placebos to claim they can cure disease. What do medical researchers usually use to make placebo pills？ A．Ivy leaves. B．Harmless leaves. C．Medicine being tested. D．sugar.

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• The quality of a batch of drug substances is judged according to

  A．product appearance B．the inspection report C．product melting point D．product color

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