A
How Can We Reduce the Risk?
There are four general approaches to dealing with volcanic(火山的) dangers.
We can try to keep the danger from occurring—often an impossible task. We can
try to change its path or reduce its impact on existing development. We can take
steps to protect future development. We can also do our best to have disaster
response plans in place before they are needed.
Removing the Threat
Clearly，there is no way to stop an eruption. We can，however，attempt to
reduce the eruption’s effects by strengthening structures，for example，building
protective works such as walls to make lava(熔岩) flow away from developed
areas. Such efforts can be and have been successful，but are of limited use in a
large-scale(大范围的) eruption.
Planning for the Future
Protecting future development from volcanic dangers is a simple task. Before
building houses，we should judge the risk. If the risk seems too great，a safer
location should be found. This type of planning is very effective，but all too often，
people are drawn to the lush(葱郁的)，rolling land of a quiet volcano.
Disaster Preparedness(预案)
When a volcano comes to life，a few weeks may not be enough time to avoid
a tragedy. Planning is the key to saving lives. Well before the warning signs occur，
people must be educated about volcanic dangers. Escape plans must be in place.
Communication between scientists，officials，the media，and the general public
should be practiced. Emergency measures must be thought out and agreed upon.
If you doubt the importance of these efforts，take another look at past
volcanic tragedies，such as the eruption of Nevado del Ruiz. Communication
failures left the town of Armero unprepared for escape. When a deadly mudflow
came down the slope( 斜 坡 ) ， 21,000 people—90 percent of the town’s
people—died.
21．The passage is intended for .
A．the general public B．architects C．adventurers D．geographers
22．When building houses，people tend to .
A．judge volcanic dangers carefully
B．take volcanic dangers seriously
C．like to live near a quiet volcano
D．find a safer place far away from a volcano
23．The writer mentioned Nevado del Ruiz to prove .
A．the failure to keep volcanic dangers from happening
B．the importance of preparing for a volcanic eruption
C．the bravery of the people in Armero Town
D．the uncertainty of volcano’s damage
