A.Tracers believe long-term effective practice Call help avoid injuries.
B.Beginners should train their endurance above all.
C.All parkour participators pay less attention to their safety.
D.Large drops are the most difficult techniques of parkour.
A.Martial art.
B.Obstacle race.
C.Gymnastics.
D.Acrobatics.
A.It helps them to digest their food.
B.It helps them to protect themselves from danger.
C.It makes it easier for them to move through the mud.
D.It makes them attractive to fish.
A.squeeze into crevices
B.devour all available food in a short time
C.suck up mud or sand
D.1ive at a low metabolic rate