Questions 47 to 56 are based on the following passage.
Some people’s ears produce wax like busy little bees. This can be a
problem even though earwax (耳垢) appears to (47) an important
purpose. Experts say it (48) and cleans the ear. It (49)
dirt and other matter and keeps insects out. Doctors think it might
also help protect against (50) . And the waxy oil keeps ears
from getting too dry. So earwax is good. It even has a medical
name: cerumen (耵聍) . There are two kinds. Most people of European or African
ancestry have the "wet" kind: thick and (51) . East Asians
commonly have "dry" earwax. But you can have too much of a good
thing. The glands (耳道) in the ear canal that produce the wax make too much in
some people Earwax is normally (52) ; it falls out of the ear
or gets washed away. But extra wax can harden and form a (53)
that interferes with sound waves and reduces (54) .
People can also cause a blockage when they try to (55)
out their ears, but only push the wax deeper inside. Earwax removal is
sometimes necessary but you have to use a (56) method or you
could do a lot of damage.