题目内容
An important new industry, oil refining(炼油), grew after the Civil War．Crude oil,or petroleum--a dark, thick ooze from the earth--had been known for hundreds of years.But little use had ever been made of it．In the 1850s Samuel M．Kier, a manufacturer in western Pennsylvania, began collecting the oil from local seepages(油苗)and refining it into kerosene(煤油)．Refining, like smelting(锻造), is a process of removing impurities from a raw material.
Kerosene was used to light lamps．It was a cheap substitute for whale oil, which was becoming harder to get．Soon there was a large demand for kerosene．People began to search for new supplies of petroleum,
The first oil well was drilled by E．L． Drake, a retired railroad conductor．In 1859 he began drilling in Titusville, Pennsylvania．The whole venture seemed so impractical and foolish that onlookers called it "Drake's Folly"．But when he had drilled down about 70 feet (21 meters), Drake struck oil;his well began to yield 20 barrels of crude oil a day.
News of Drake's success brought oil prospectors(探寻者)to the scene, By the early 1860 s these wildcatters(盲目采油者)were drilling for "black gold" all over western Pennsylvania．The boom rivald the California gold rush of 1848 in its excitement and Wild West atmosphere,And it brought far more wealth to the prospectors than any gold rush.
Crude oil could be refined into many products.For some years kerosene continued to be the principal one．It was sold in grocery stores and door to door．In the 1880s and 1890 s refiners learned how to make other petroleum(石油) products such as waxes(石蜡)and lubricating oils (润滑油)．Petroleum was not then used to make gasoline or heating oil.
第 31 题 What is the main idea of the passage？
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A．acceptedB．questionedC．confirmedD．favored
根据材料请回答 51～65
Can Loud Music Cause Hearing Impairmen？
Have you ever gone to a concert and realized that your seats were right next to the booming speakers？ Are you guilty 51 turning up the volume on your portable cassette or CD player to drown out the whining of your little brother？ Sometimes it's difficult to avoid loud music or noises，but they can be bad news because loud noises can 52 temporary or permanent hearing loss．
Extremely loud music and noise that go on for long periods of 53 are common causes of deafness．If a noise is so loud that you have to shout to make yourself 54 (which hap—pens a lot when you use machinery in wood or metal class at school or when you go to a concert)，there is a 55 that the mechanism inside your ear can be injured.
Temporary hearing loss can happen after you’ve been 56 to loud noise for only 15 minutes．If you have temporary hearing loss，you won’t be able to hear as 57 as you nor— mally can，and you may have tinnitus，which is a fancy word for ringing in the ears．Your ears can feel“full”，too． 58 ，these things usually go away and your hearing soon returns to normal．
Permanent hearing loss can happen when someone is exposed to loud noise 59 and over．Construction workers and people 60 work in factories must wear ear protection be—cause the equipment they use can be extremely loud.But even some lawn mowers and power tools can permanently 61 a person’s ability to hear high-pitched noises and can al—so give him permanent tinnitus .Listening to extremely loud music over and over can also have the same effect on a person’s 62 ．And using headphones on a portable cassette or CD player can be dangerous 63 if the volume is too high and the headphones are used a lot，the noise can damage the ears．
The best way to avoid hearing loss is to wear ear protection when working with ma— chinery and earplugs when going to a 64 ．Headphones are OK to wear when you’re lis— tening to music；just be sure the volume isn’t up too high，and give them a rest 65 0nce in a while.
第 51 题
The most densely populated continent is________.
People start to pay more attention to food waste.
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