Jogging is becoming one of the 21_____ growing activities in the nation． More people are starting jog each year． This, however, is a recent occurrence． It was not long ago 22_____ joggers were rare sight． Some people thought that they looked quite strange． As 23_____ people began jogging the sight of them became more common.
There are many reasons 24_____ a person to take up jogging． First, it is a good form of exercise．This is 25_____ it involves the use of many parts of the body． The exercising of the heart is of great benefit． This is one of the most important parts of the human body． If the heart does not get the needed exercise, serious problems can occur．
26_____ reason for jogging is for enjoyment．27_____ being good for people, it can also be very much fun．
Part of the fun of jogging comes from the opportunity it provides for meeting other people who enjoy it．
One 28_____ that should be considered 29_____ a person takes up jogging as a form of exercise of enjoyment is that it is not for everyone． People should first check, 30_____ their doctors and be prepared to find another form of exercise if jogging is not recommended.
21．
A.fastest B.quickest C.most D.best正确答案A
