13．This year is a leap year．Leap years are years with 366days，instead of the usual 365．Leap years are necessary because the actual length of a year is 365.242days，not 365days，as commonly stated．Basically，leap years come every 4years，and most years that can be evenly（平均地） divided by 4have 366days．This extra day is added to the calendar on February 29
th which is known as a leap day．Why leap is used here？Leap means jump．
However，there is one exception to the leap year rule about century years．Century years are only considered as leap years if they are evenly divided by 400．Therefore，1900was not a leap year，but 2000was a leap year．
A person who is born on February 29
th may be called a"leapling"or a"leap year baby"．In non-leap years，some leaplings celebrate（慶祝） their birthday on either February 28
th or March 1
st．In England and Wales or in Hong Kong，a person born on February 29
th，1996，will have legally（法律上） reached 18years old on March 1
st，2014．If he or she was born in the United States，Taiwan or New Zealand，his or her legally birthday will come a day earlier．
There is a popular custom in some countries that a woman may ask a man to marry her on February 29
th．If the man refuses，he then has to give the woman money or buy her a dress．
Since leap days are special days，people nowadays want to do something different within the 24extra hours．Big jumps are the most popular ones．
Some salaried（領(lǐng)薪水的） workers want to get pay for their extra day's work．But in my opinion，if you know why there is a leap day，you will get the answer to this problem．
52．The next leap year isB．
A.2014
B.2016
C.2018
53．American boy Toby is a leapling．Next year he will probably to have his birthday party onA．
A．February 28
th B．February 29
th C．March 1
st54．Which picture is about popular custom on leap days？B
55．Many people like to have a big jump on leap days probably becauseC．
A．it's a custom
B．they are leaplings
C．leap means jump
56．We can learn from the passage thatA．
A.2100will not be a leap year
B．every year leaplings celebrate their birthday on either February 28
th or March 1
stC．it is necessary to pay the salaried workers for the leap day's work．
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