The exposition is the very beginning of the story so it should introduce the characters and the setting and maybe introduce a lesson to be learned.
It would be a comprehensive description and explanation of an idea.
Answer: In general, use sentences of different lengths. Also consider moving adverbs or adverb clauses from the end of a sentence to the beginning.
For transitions, think about the relationship between ideas. Is it a time sequence? Use words like first, then, after that, finally. If it's logic, use words like because, since this... then that. Or therefore, as a result.
Explanation:
