Use each clue to write a sentence in the subjunctive mood 13 through 16

Subjuntive Mood is rarely used in English. It expresses ideas, wishes and counterfactual situations.

13- If I were you I would travel a lot. (it is contrary to fact because I cannot be you).

14 - It is paramount that he practice everyday. (in this case Subjunctive Mood is used in a "that clause").

15 - I wish you were here. (in this case Subjunctive Mood is also expressing a counterfactual situation because it is implicit that "you are not here").

16- It is crucial that he call me as soon as he arrives at home. (note that in "that he call me" the verb is not conjugated in the third person which is a characteristic of Subjunctive).

c, his tragic flaw to cause his downfall