问题详情：
On Oct.8, 1871, much of Chicago became an inferno（地狱）. The fire began in or near the O'Leary family's barn（仓库）. No one knows for certain how it started, but it developed into a big fire that consumed miles of city, killed about three hundred people, and left about one hundred thousand homeless. Many conditions may have contributed to the Great Chicago Fire.
Dry weather was one possible factor. The summer and autumn had been unusually dry, and 20 fires occurred the week before the Great Fire. Just the night before, the city's firefighters battled a severe fire, and many were exhausted. Besides firefighters' being very tired, the Chicago Fire Department was understaffed and inadequately equipped.
Also, most buildings were wooden, and many were crowded together. Even sidewalks were wooden, and rooftops were of shingles or tar --- both flammable (易燃的) materials. Interspersed（点缀） between residences were warehouses and business, some containing paint and other flammable merchandise.
Although a citizen had surely sounded an alarm, the central alarm office had no record of it. Possibly the alarm failed to work properly. To make things worse, a watchman scanning the skies for fire misjudged the location and sent an alarm that caused firefighters to rush to an incorrect site. Realizing his error, the watchman tried to send a second alarm, but the telegraph dispatcher（调度员） refused to allow it, fearing that it would confuse the firefighters. These errors caused the fire to grow quickly out of control before firefighters reached the scene.
Lacking telephones, radio and TV in 1871, few people in Chicago realized the severity of the fire until they had to scramble to escape it. Some people rushed into Lake Michigan to escape the flames, while others fled to the prairie（大草场） or elsewhere. Meanwhile, troops and civilians blew up buildings to create a firebreak, hoping that it would contain the fire or, at least, slow its progress.
strong winds blew burning ashes onto buildings and across the Chicago River, causing the fire to spread still farther. The fire lighted the oil and boats floating on the water and caused the gasworks to explode. It burned the wooden roof of the waterworks, which collapsed and destroyed the city's water pumps. Unless firefighters could pump water from the river or lake, they were helpless to stop the blaze. Just when it appeared that nothing would stop the big fire that roared through the city, rain fell on Oct. 10 and contained the fire.
(Note: Answer the questions or complete the statements in NO MORE THAN TEN WORDS.)
76. Dry weather, flammable materials,_______ and ________________made the fire spread quickly.
77. The phrase "contain”in the passage most probably means "______________ " .
78. What made these firefighters so tired before they began to put out the fire?
_________________________________________________
79. Why couldn't these firefighters get water to put out the fire?
__________________________________________________
【回答】
strong winds, human errors.
stop; control; prevent.
They battled / put out a fire just the night before. /They went to a wrong place.
(Because) the city's water pumps were destroyed in the fire.
知识点：科普环保类阅读
题型：阅读理解
