Answer:
To give writing versatility and allow the reader to have a greater understanding of the meaning conveyed by the text.
Step-by-step explanation:
When a writer uses a variety of sentences in his text, he shows not only the versatility of his writing, but the concern that the reader will be able to understand the meaning of the text in a dynamic and exciting way.
This is because the variety of sentences leaves the text dynamic and allows each sentence to complement the other by showing ideas that provide the basis for statements, support and even explanations.