在英语越来越普及的21世纪，学好英语成了大学生最重要的目标。为帮助大学生更好地学好英语，特提供以下文章：
英语专四听写模拟操练：危机
Crisis
Life is a contest! Who will win? A bluebird and sparrow both compete for space to build their nests. A fast-growing maple tree and slower-growing dogwood compete for the sunlight they both need. Oil competes with coal and nuclear power as an energy source for electric power plants!
There is a problem. There is a limited amount of space for birds, sunlight for trees, and energy for people! If we do not cut back on our uses of some of our resources, someday they will be gone!
How can we use energy today and know we will have enough to go around in the future? We can choose alternate, or replacement, energy resources. It takes the earth millions of years to create coal, oil, and gas. They are nonrenewable resources.
Solar energy, wind energy and water energy are renewable resources. It takes the earth millions of years to create coal, oil, and gas. They are nonrenewable resources.
Solar energy, wind energy and water energy are renewable. What other ways can we conserve our sources? How can we make sure there is always enough to go around?
Useful words and expressions:
bluebird 蓝知更鸟
sparrow 麻雀
dogwood 山茱萸
power plant 发电厂，发电站
alternate 替代物
nonrenewable resources 不成再生资本
conserve 保留，保藏
Time
Time is tangible. One can gain time, spend time, waste time, save time, or even kill time. Common questions in American English reveal this concrete quality as though time were a possession. “Do you have any time?”, “Can you get some time for this?”, “How much free time do you have?” The treatment of time as a possession influences the way that time is carefully divided.
Generally, Americans are taught to do one thing at a time and may be uncomfortable when an activity is interrupted. In businesses, the careful scheduling of time and the separation of activities are common practices. Appointment calendars are printed with 15-,30-, and 60-minute time slots. The idea that “there is a time and place for everything” extends to American social life. Visitors who drop by without prior notice may interrupt their host’s personal time. Thus, calling friends on the telephone before visiting them is generally preferred to visitors’ dropping by.
Useful words and expressions:
tangible 切实的
kill time 消磨时刻
reveal 显示，揭示
scheduling 行程放置
slot 裂痕
drop by 随便访谒
preferred 首选的