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 the initial steps in changing habits. This is an introductory statement that sets the stage for the rest of the text. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone as the first sentence. For example, Paragraph 2 starts with 'It was crucial,' which is a pronoun that refers back to something not yet mentioned. Paragraph 3 starts with 'The transformation,' which uses 'the' and assumes prior knowledge. Paragraph 4 starts with 'Seeing,' which is not a general statement.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the text by showing the results of the changes. It summarizes the positive effects and reflects the overall theme of maintaining new habits.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it explains why planning is important. The phrase 'It was crucial' shows that understanding the process is necessary after identifying habits.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it gives examples of the gradual changes mentioned. The phrase 'The transformation began' shows the next step after understanding the process.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it talks about the results of the changes. The phrase 'Seeing the positive effects' shows the outcome of the transformation.