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 book. It gives a broad overview of what the book is about without going into details. It does not use any pronouns or definite articles that would need prior context. Why other lines are not chosen? Paragraph 2 starts with 'At SAS,' which needs more context. Paragraph 3 starts with 'He began,' which refers back to a person, so it is not independent. Paragraph 4 starts with 'By the time,' which also needs context from earlier sentences.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it concludes the story of Carton’s journey. It shows the situation he faced at SAS, which wraps up the main theme of his experiences.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it gives a specific example of Carton’s activities at Vingresor. This follows the Broader to Specific Strategy, where the first paragraph introduces the book and the second paragraph gives a specific story.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it shows how Carton changed after his time at Vingresor. This follows the Logical Order rule, as it shows the progression of his learning and growth over time.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it shows the next step in Carton’s journey after Linjeflug. This follows the Chronological Order rule, as it continues the timeline of his career.