Extreme sports are sports _________ are known to be of high risk or speed, such as snowboarding, skydiving or freestyle skiing.
which
15
Extreme sports are all about _______ thrill of it.
the
15
Some people do them just ________ fun, while others really test the limits of what is humanly possible.
for
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Extreme sports first ________ popular in the 1990's and appeals mostly to the younger generation.
became
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The most well-known extreme sports competition began ________ the USA in 1995, and is called the ‘X Games’.
in
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The X games are held annually, ________ in the summer and winter.
both
15
The X Games are held in the summer and winter, in order to cater _______ all the major extreme sports.
for
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People who compete in such events do it mainly for the adrenaline rush that potential danger provides. However, just ________ the Olympics, there are many other incentives.
like
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The competition awards medals and a cash prize to those ________ are successful.
who / that
15
The effects of insufficient sleep ______ teenagers can be quite dramatic, even more so than in adults.
on
15
As according ______ research, young people are biologically driven to require more sleep.
to
15
A lack ______ sleep for teenagers can cause low mood swings.
of
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Teenagers not getting enough sleep can cause low mood, behavioural problems ______ an inability to concentrate.
and
15
A recent report revealed that teenagers not sleeping enough was, ______ fact, becoming an increasingly significant issue.
in
15
Researchers found that the average amount of sleep that teenagers get is between 7 and 7.25 hours per ______ .
night
15
Studies show that teenagers actually need 9.25 hours of sleep in ______ to function well, physically and psychologically.