Are these sentences that you had to write?
Sentence 2 is a bad sentence in many ways.
A leash is the means by which people lead their dogs and other animals.
Sentence 3
A wizard is a person versed in magic and esoteric knowledge.
Sentence 4 - look them up in a dictionary:
OneLook Dictionary Search
Sentence 5 - the meaning of this is not clear. Do you mean "Currently I am standing at the back entrance to the University"? or "Currently I am about to take the University entrance examination"?
Sentence 6 - There is an old and now largely unused colloquial use of "wizard" as an adjective to say a person is a particularly great personality. If that is not the intention of the sentence, which is saying that this person is a wizard, then yes, person should be omitted.
Sentence 7 - Why does reading a historical story make you marvelous?
Sentence 8 - neither is incorrect
Sentence 10 correct
Sentence 11 - what do you mean by "currently" in this sentence?
Sentence 12 - all three can be correct, depending on the full context.
Sentence 13 - do you mean that because your father called you about something that is dramatic, you went home. If not, what do you mean by "dramatically"?