(2019·河北黄骅中学模拟)Of all nature 's disasters，forest fires are often considered the most frightening.Moving at lightning speed，huge walls of flames can burn acres of land in just a few minutes.And although technology，including the use of fire－retardant chemicals，has greatly helped the fight against forest fires，they still do great damage.
According to the National Interagency Fire Center，the fire season last year was the worst on record in terms of the number of fires and acres burned.There were 96.385 fires and 9.873429 acres affected by fire in a year that was125% more destructive(毁灭性的) than the10－year average.These fires cost the federal government $1.5 billion to fight，and this figure does not include the money spent by local and state governments as part of the effort.
Fires in the southern states represented half of the national total last year with Texas，Oklahoma and Arkansas being home to a usually high amount of activity.Wildfire has also taken place in Western states such as California，Colorado and Alaska throughout the past 10 years.
It is said that two－thirds of forest fires are started accidentally by people.Almost one quarter are purposely set，while lighting causes 10%.
Forest fires can have advantageous effects.Charcoal(木炭)enriches soil and some plant species(种类) grow well after fire.The cones of the jack pine tree，for example，will not spread their seeds unless there is heat.Douglas fir trees grow best in open sunlight areas after fire.
【语篇解读】 本文主要讲了森林火灾被认为是最令人害怕的，因为它们蔓延得太快，造成的损失太巨大。作者对造成森林火灾的原因进行了分析，并且说明了森林火灾也有一些优点。
1．Forest fires are considered to be the most frightening because ________.
A．fire－retardant chemicals can't be made use of
B．huge walls of flames can burn acres of land
C．they make the greatest loss of all disasters
D．they spread too fast and do great damage
【答案】 D 细节理解题。由Moving at lightning speed，huge walls of flames can burn acres of land in just a few minutes.And although technology，including the use of fire－retardant chemicals，has greatly helped the fight against forest fires，they still do great damage.可知森林火灾被认为是最令人害怕的，是因为它们蔓延得太快，造成的损失太巨大，选D。
2．Almost 25% forest fires are set ____.
A．unexpectedly B．by lighting
C．on purpose D．naturally
【答案】 C 细节理解题。由Almost one quarter are purposely set，while lighting causes 10%.可知几乎25%的森林火灾是被故意点燃的，选C。
3．What does the last paragraph mainly talk about?
A．The advantages of forest fires.
B．The usage of charcoals.
C．Pine trees need fires.
D．Fires destroy all plants but two.
【答案】 A 段落大意题。由最后一个段落的主题句Forest fires can have advantageous effects.可知最后一个自然段主要讲了森林火灾的一些好处，选A。
