Avoid the primer style.
Untrained writers sometimes try to express in simple sentences ideas that could better be put in subordinate, coordinate, or parenthetical constructions. Although occasional simple sentences can be emphatic and effective, too many in succession are reminiscent of Dick and Jane. In order to avoid this transgression, combine simple sentences into longer ones, substitute pronouns for repeated subjects, and use subordination.
1. Ruth did much for Naomi. Ruth was almost like a servant to Naomi. She gathered grain in the fields of Boaz for Naomi's meals. Boaz was a distant relative of Naomi. Ruth, by her actions and personality, impressed Boaz very favorably. He was therefore willing to give a large amount of grain to Naomi.
Better: Ruth was almost like a servant to Naomi. She gathered grain for her in the fields of Boaz, Naomi's distant relative. By her kindness, she so impressed Boaz that he willingly gave...
2. In the admissions office was a group of people. They comprised a group of five prospective students and their parents. They were waiting to take a tour of the campus.
Better: A group of prospective students and their parents gathered in the admissions office, waiting to take a tour of the campus.