题目内容
That earthquake damaged many houses and business buildings; ______ , it caused 400 deaths .
A. or else B. therefore C. after all D. besides
D
解析:
略
If your cellphone suddenly stops working, don’t blame the service provider.The malfunction(故障) might well have been caused by something bigger -- a solar storm.Experts expect that Earth will see more solar activity in the near future.The malfunction of electronic devices will just one of the effects.
Sunspots(太阳黑子) serve as an indicator of the sun’s activity.For the past two years, sunspots have mostly been missing.Their absence, the most prolonged in nearly 100 years, has taken even seasoned sun watchers by surprise.
When the number of sunspots drops at the end of each 11-year cycle, solar storms die down and all become much calmer. This “solar minimum” doesn’t last long. Within a year, sunspots and solar storms begin to build toward a new crescendo, the next solar maximum.
What’s special about this latest cycle is that the sun is having trouble starting the next solar cycle. The sun began to calm down in late 2007, so no one expected many sunspots in 2008. They should return in 2010. Scientists have predicted that the next solar cycle could be the most active on record: more sunspots and more solar storms. However, sunspots are mostly missing now.
Since the earth is in close contact with the sun, strong solar activities can bring trouble to our life. People of the 21st century rely on high-tech systems for the basics of daily life. Air travel and radio communications can be affected by strong solar activities. A big solar storm could cause 20 times more economic damage than Hurricane Katrina.
What the sun will do next is beyond our ability to predict. Most astronomers think that the solar cycle will go on but at low level. However, there is also evidence that the sun is losing its ability to produce sunspots. By 2015, they could be gone altogether.
【小题1】The sun watcher feel surprised at .
A.the longest sunspots’ absence | B.the largest sunspot number |
C.the malfunction of electronic devices | D.the serious damage by sunspots |
A.small number | B.high level |
C.usual cycle | D.fresh start |
A.solar activities have brought much trouble to our life |
B.the number of sunspots has increased to a large extent |
C.the solar minimum took the place of the solar maximum |
D.our cellphones have seldom been interrupted by the solar storm |
A.Solar activities do no harm to our daily life. |
B.Hurricane Katrina is also a type of solar storms. |
C.It’s difficult to predict sunspots. |
D.From now on there’ re no sunspots. |
A.The earth is in close contact with the sun. |
B.Sunspots can cause trouble to our life. |
C.Introduction of sunspots. |
D.Introduction of the solar storm. |