A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic about rivers. It is a general statement that does not need other sentences for context. It does not start with a conjunction or use pronouns. It sets the stage for the discussion about rivers. Why other lines are not chosen? Paragraph 2 starts with "Perhaps" which is a conjunction, so it is not independent. Paragraph 3 uses "the" which assumes prior knowledge of rivers, making it not independent. Paragraph 4 starts with "No matter" which is also a conjunction. Paragraph 5 starts with "Sometimes" which is a conjunction too.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the discussion about river flow directions. It summarizes the main points and gives a final thought on the topic.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues the idea of misconceptions about rivers. It uses the Connector strategy to show that both paragraphs talk about what people think about rivers.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it gives the truth about rivers after discussing misconceptions. This shows a Logical Order where the truth follows the misconceptions.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it explains what happens when rivers flow downhill. It uses the Broader to Specific Strategy, where the truth is followed by a specific detail about river flow.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 connects with Paragraph 4 because it gives examples of the directions rivers can flow. This shows a General to Specific progression, where the general idea of river flow is followed by specific directions.