First sentence: Why this is the first line? This paragraph is the first because it introduces the main topic of preparing ingredients. It is a general statement that does not need another sentence for context. It sets up the process of making lasagna without diving into specifics. Why other lines are not chosen? Paragraph 2 starts with 'Start cooking', which is not independent because it needs context. Paragraph 3 starts with 'While the meat sauce simmers', which refers to a previous action. Paragraph 4 starts with 'Finally', which indicates it is not the first step.

Concluding sentence: Why this is the last line? This paragraph is the last because it wraps up the cooking process. It uses the word 'Finally', which signals the end of the steps in making lasagna.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues the process of making lasagna. The logical order is clear as you prepare ingredients first and then start cooking.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it describes what to do while the meat sauce is cooking. This shows a chronological order of steps in the recipe.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it describes the final steps after preparing the ricotta mixture. This shows a logical order of the cooking process.