Fill in each numbered blank with one suitable word or phrase.

            Why is it that many teenagers have the energy to play computer games until late at night but can't find the energy to get out of bed (1) _____ time for school? According to a new report, today’s generation of children are in danger of getting so (2) _____  sleep that they are putting their mental and physical health at (3) ________. Adults can easily survive on seven to eight hours' sleep a night, (4)_____ teenagers require nine or ten hours. According to medical experts, one in five youngsters (5) ______ by on between two and five hours/ sleep a night, less than their parents did at their age.

Why is it that many teenagers have the energy to play computer games until late at night but can't find the energy to get out of bed  (1) _____ time for school?