We've all been there,running for a bus or train on a cold morning only to find that our nose is also running! Grab some tissues and learn the science behind the phenomenon known as"skier's nose."
 A nose like a running tap in winter is business as usual for many people.People call it"skier's nose".In a study,researchers found that 96 percent of people surveyed reported experiencing some degree of the condition.
Apparently,getting a runny nose in cold weather is a bodily defense reaction.That's because the nose has two main purposes:1)to filter bacteria so they don't reach our lungs,and 2)to warm and humidify(加湿）the air before it reaches our lungs. Our airways are lined with tiny hairs known as ciliA.In the nose,these cilia wave back and forth to remove our mucus(黏液）so that bacteria can be blocked out.In cold weather the cilia are slowed.When cilia slow,bacteria remain in place and multiply,and this is why people get sick in winter.Not that the nose isn't trying to keep you healthy.All that running nose experience is the nose working overtime to produce more liquid to help move bacteria along.To help it out,experts say that you can try physically warming your nose:Rub your hands together,and then breathe into cupped hands or draw in steam from hot green tea and drink it,as green tea helps accelerate the growth and functioning of cilia.
Our nose runs in winter for one more purpose,which is to fight against the drier outside(and inside)air.In winter,or when it's cold outside,the air is much drier than in summer.Our noses respond by producing more liquid to help humidify the air to a level our bodies need,and that's when it starts to run out of the end of our nose.
24.What does the underlined word"filter"probably mean in the third paragraph?
A.Kill.           B.Prevent.                  C.Defend.               D.Trap.
25.What can we know about"cilia"?
A.They only exist in the nose.
B.They stop working in winter.
C.They can sweep away mucus.
D.They help break down bacteria
26.Which of the following is the best title for the text?
A.When Do You Have A Running Nose?
B.What Are the Purposes of Your nose?
C.How Can You Deal With
D. Why Does.Your Nose Run When It's Cold?,
 24-26 BCD