共用题干 第一篇

Food Poisoning

Food sometimes gets poisoned with harmful things,A person who eats such food can get an illness called
food poisoning. Food poisoning is usually not serious,but some types are deadly.The symptoms of food poi-
soning usually begin within hours of eating the poisoned food.Fever is one of the most common symptoms.
Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms
can poison eggs,meat,vegetables,and many other foods.After entering the body,these tiny living things re-
lease（释放）poisons that make people sick.
Some chemicals can also cause food poisoning. They are often added to food while it is being grown,pro-
cessed,or prepared.For example,many farmers spray chemicals on crops to kill weeds and insects.Some
people may have a bad reaction to those chemical、when they eat the crops.
Some plants and animals contain natural poisons that are harmful to people.These includo certain kinds
of seafood,grains,nuts,seeds,beans,and mushrooms.
When people handle food properly,the risk of food poisoning is very small.Microorganisms multiply rapidly
in dirty places and in warm temperatures.This means that people should never touch food with dirty hands or
put food on unwashed surfaces.Food should be kept in a refrigerator to stop microorganisms from growing,
Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered
with chemicals before eating it.Finally,people should not eat wild mushrooms or other foods that grow in the
wild.Some of these foods may contain natural materials that are poisonous to humans.In addition,some types
of fish can be poisonous.
Most people recover from food poisoning after a few days of resting and drinking extra water. If people
eat natural poisons,they must go to the hospital right away to have their stomachs emptied.

单选题That performance was pretty impressive.

单选题She read a poem which depicts the splendor of the sunset.

单选题Will you please call my husband as soon as possible?

单选题共用题干 第三篇<br><br>Ways to Create Colors in a Photograph<br><br>There are two ways to create colors in a photograph.One method called additive,starts with three basic colors and adds them together to produce some other color. The second method,called subtractive,starts with white light(a mixture of all colors in the spectrum)and,by taking away some or all other colors,leaves the one desired.<br>In the additive method,separate colored lights combine to produce various other colors.The three additive primary colors are green,red and blue(each providing about one-third of the wavelengths in the total spectrum).Mixed in varying proportions,they can produce all colors.Green and red light mix to produce yellow,red and blue light mix to produce magenta(a purplish pink);green and blue mix to produce cyan(a bluish green).When equal parts of all three of these primary-colored beams of light overlap（重叠）,the mixture appears white to the eye.<br>In the subtractive process colors are produced when dye（染料）absorbs some wavelengths and so passes on only part of the spectrum.The subtractive primaries are cyan,magenta and yellow; these primaries or dyes absorb red,green and blue wavelengths respectively,thus subtracting them from white light. These dye colors are the complementary colors to the three additive primaries of red,green and blue.Properly combined,the subtractive primaries can absorb all colors of light, producing black.But,mixed in varying proportions,they too can produce any color in the spectrum.<br>Whether a particular color is obtained by adding colored lights together or by subtracting some light from the total spectrum,the result looks the same to the eye.The additive process was employed for early color photography. But the subtractive method,while requiring complex chemical techniques,has turned out to be more practical and is the basis of all modern color films.

单选题The governor gave a rather vague outline of his tax plan.

单选题The police arrested the suspect yesterday and released him this morning.

单选题共用题干 Vision<br><br>Human vision like that of other primates（灵长目）has evolved in an arboreal（丛林）environment.______(46)<br>In the course of evolution,members of the primate line have acquired large eyes while the nose has shrunk.______ (47) Of mammals（哺乳动物）only humans and some primates enjoy color vision.______(48)Horses live in a single-color world.<br>Light visible to human eyes,however,occupies only a very narrow band in the whole electromagnetic spectrum（光谱）.Ultraviolet rays（紫外线）are invisible to humans though ants and honeybees are sensitive to them.______(49)The world would look terribly different if human eyes were、 sensitive to infrared radiation（红外线）.Then instead of the darkness of night,we would be able to move easily in a strange shadowless world.______(50)<br>But human eyes excel in other ways. They are in fact remarkably discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by complicated technical devices.

单选题The book took ten years of thorough research.

单选题John is crazy about pop music.

单选题Jess likes playing basketball，but I like swimming.