rest of the sun’ s surface sunspots are frequently observed’in-'pairs of in paired groups.the members of a.spot pair are identified as the leading spot and the following spot.they are identified by their position in the pair in terms of the direction in which the sun rotates(旋转) the number of sunspots at any one time varies.a large spot group may consist of as many as 10 groups and 300 spots across the sun.the number of spots changes in a fairly regular pattern called the sunspot cycle.the largest number occurs about every 11 years.at sunspot minim l{m，there are at most just a few small spots the average lifetime of an individual spot group is roughly one solar rotation，whic he is about 25 days.the most persistent large slops，however can survive for two to three months.
31. careful observations and systematic studies of sunspots
a. were made by ancient astronomers.
b. started in the early 17thcentury.
c. were made by galileo only.
d. could be made without a telescope.
32. sunspots are cooler than the rest of the sun's surface because
a. they produce less energy.
b. they are buried in the sun.
c. they are far away from magnetic fields.
d. they are close to magnetic fields.
33 the leading spot and the following spot are the names of
a. two large sunspots.
b. a large spot and a small spot.
c. the two spots in a spot pair.
d. the central core and the ring around it.
34. infiniteness sunspot activity had occurred in 1857, the next one would have been in
a. 1858.
b. 1862.
c. 1865(www．。com)
d. 1868
35 in the last paragraph the word "persistent means
a. important.
b. effective.
c. enduring.
d. visible.
第二篇 where have all the bees gone?
scientists who study insects have a real mystery on their hands.all across the country, honeybees are leaving their hives(蜂巢)and never returning.researchers call this phenomenon colony-collapse(群体瘫痪)disorder.it is reposed that 25 to 40 percent of the honeybees in the us have vanished from their hives since last fall.so far, no one can explain why.
colony collapse is a serious concern because bees play an important role in the production of about one—third of the foods we eat.as they feed，honeybees spread pollen (花粉)from flower to flower.without this process，a plant can’t produce seeds or fruits.
now，a group of scientists and beekeepers have teamed up to try to figure out what’s causing the alarming collapse of so many colonies.they hope to find out what’s contributing to the decline and to prevent bee disappearance in the future.
it could be that disease is causing the disappearance of the bees.to explore that possibility, jay evans，a researcher at the united states department of agriculture (sda)bee research laboratory, examines bees taken from colonies that are collapsing.“we know what a healthy bee should look like on the inside.and we can look for physical signs of disease.”he says.and bees from
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