PLEASEE HELPP MEE!!?? DUEE SOON, WILL GIVE BRAINLIESTT,

Many teenagers regularly do not gets enough sleep. The hormonal change during puberty causes the body clock to (9) shifted by about one or two hours. This makes them sleep later. (10) Later they sleep later, school starts early and they are forced to get up early. This causes (11) they not to have enough sleep. Hectic after-school schedules like homework, sports, part-time work (12) so social commitments can cut into a teenager’s sleeping time. Leisure (13) activity such as television-watching, Internet surfing and computer gaming can (14) keeps a teenager out of bed. These activities cause the brain to stay awake. (15) The active brain makes it even more (16) difficulty to fall asleep. Lack of sleep can cause difficulties to concentrate in class and short attention spans. It can also cause moodiness, aggression and inability to remember facts learnt. The result is thus a fall in the grades of examination.

9) shifted -
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13) activity -
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16) difficulty -
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