A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of the text. It talks about how life has made it hard to read for pleasure. This is a general statement that sets the stage for the rest of the text. It does not use any words that need prior context. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with 'A chance encounter,' which needs context. Paragraph 3 uses 'Setting aside,' which also needs context. Paragraph 4 starts with 'This renewed habit,' which refers back to something not yet mentioned.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the ideas. It shows the benefits of reading more. It uses words like 'has not only... but also,' which signal a conclusion. This makes it clear that the text is ending.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it shows a change. The first paragraph talks about losing the habit of reading, and the second talks about finding it again. This is a logical order of ideas.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it explains what happened after finding the old book. It shows the action taken to read more, which is a clear flow of ideas.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about the results of the new reading habit. It shows how reading more has helped the writer feel better, which is a logical conclusion.