A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main action of the event. It shows the starting point of planning the barbecue. It does not refer to anything before it, so it is independent. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with 'Finalising the menu,' which needs context. Paragraph 3 starts with 'To make the event more enjoyable,' which also needs prior information. Paragraph 4 starts with 'On the morning of the barbecue,' which assumes the event is already planned. Paragraph 5 starts with 'Before we knew it,' which refers back to earlier actions.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the events of the barbecue. It shows the final result of all the planning and preparation. It gives a sense of completion to the story.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it follows the planning process. The first step is sending invitations, and then the next step is finalising the menu. This shows a logical order of actions.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it continues the planning of the barbecue. After finalising the menu, the next step is deciding on the sides. This shows a logical order of ideas.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it shows what happens next. After deciding on the sides, the next action is preparing the food. This shows a clear flow of ideas.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 connects with Paragraph 4 because it describes the result of the preparation. After marinating and prepping, the table is ready. This shows a cause and effect relationship.