(6) What does "occurs" , in the second paragraph, mean?
أ) ) work
ب) ) does
ج) ) happens
د) ) dream
(7) The underlined pronoun "others" in the last paragraph, refers to….
أ) ) things
ب) ) scientists
ج) ) minutes
د) ) occurs
(8) Why should we sleep according to the first theory?
أ) ) we sleep to dream.
ب) ) we sleep to remember things.
ج) ) we sleep to repair our bodies.
د) ) we sleep for no reason