A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main idea of writing an essay. It does not need other sentences to understand it. It talks about how a good essay comes from a plan, which is a general statement. This follows the rule of Topic Sentence. Why other lines are not choosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with 'Using a plan', which needs the first sentence for context. Paragraph 3 starts with 'Once you've organized', which also needs prior information. Paragraph 4 starts with 'Remember', which is not clear without earlier sentences.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the ideas about writing an essay. It gives a final thought that is important for the reader. This follows the Conclusive Words rule, as it reminds the reader that the first draft can be improved later.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it explains more about the plan mentioned in Paragraph 1. This follows the Broader to Specific Strategy. Paragraph 1 talks about the importance of a plan, and Paragraph 2 gives details on how to use that plan.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it shows the next step after using a plan. This follows the Logical Order rule. After you figure out your main ideas, you can organize them and write your draft.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it gives advice about the first draft. This follows the Cause and Effect Relationship rule. After you write your first draft, it is important to remember that it does not need to be perfect.