An opening sentence should name the paragraph's topic. A closing sentence should land the point, not start a new one. Placement as a set is in macro logic.
First and last have jobs
A first sentence that assumes a detail from later in the paragraph is in the wrong spot. A last sentence that introduces a new example belongs earlier, or not at all. Writer's-goal stems often sit here, in writer's-goal questions.
Sentence order inside the paragraph is in sentence-order questions. Question types are in English question types.
The bottom line
Open with the topic. Close with the point. Do not open a new door at the end.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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