First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic about tides. It does not need other sentences to understand it. It gives a general idea about tides. This follows the rule of Topic Sentence. Why other lines are not chosen? Paragraph 2 starts with "The greatest" which makes it specific and not general. Paragraph 3 starts with "In France" which also makes it specific. Paragraph 4 starts with "This is one way" which refers back to something else. All these sentences do not stand alone without context.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the topic. It shows the conclusion of the discussion about tidal power. It explains the importance of the previous information. This follows the Conclusive Words rule.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it gives a specific example of a tidal range. This follows the Broader to Specific Strategy. The first sentence talks about tides in general, and the second gives a specific case.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it continues the topic of tidal ranges. It gives another example of a tidal range in France. This follows the Logical Order rule, as it keeps the same subject of tidal ranges.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about what scientists are doing with tidal power. This follows the Cause and Effect Relationship rule. The third paragraph shows the example of a tidal power station, and the fourth explains the purpose of such projects.