Why are we so tired?

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Across
  1. 3. not enough of something
  2. 5. lack of sleep
  3. 8. Being poor and bad standard of something
  4. 10. having a awful memory of something
  5. 11. having a difficulty of doing things
  6. 12. to be still, quiet and restful
  7. 14. Sleeping but not sleeping at the same time
  8. 15. To damage something or someone
Down
  1. 1. something that has been harmed or weak
  2. 2. changes of emotions very fast
  3. 4. something or someone that is little
  4. 6. to have new spirit or power
  5. 7. to maintain something
  6. 9. saliva that falling out of your mouth
  7. 13. An illness that continues for a long time