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Exams have begun/started. I am afraid/frightened of them. I don't like Arabic.

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Exams begin (soon). I am afraid, of because I don't like Arabic.

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I am afraid because my exams are beginning (this week).

Exams begins. I am afraid of. I don't like Arabic.

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Exams begins. I am afraid of them. I don't like Arabic.

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Exams begin (as it is a plural, you won't add this "s". You only add "s" if you have a personal pronoun: he,she or it)  s. I am afraid because of. I don't like Arabic. 

Don't be afraid. Just learn as effective as it's possible and everything is going to be ok.

I also hated mathematics and history during my education, but I learned and I passed these exams. 

Com'on girl, I know you can do it and be positive. 

Good night.