First sentence: Why this is the first line? This paragraph is the first line because it introduces the main topic of the text. It gives a broad overview of the changes in computer storage. It does not refer to any previous information, so it stands alone. This follows the rule of Topic Sentence. Why other lines are not chosen? The other paragraphs are not chosen because they do not meet the criteria for being independent. For example, Paragraph 2 starts with 'Early computers,' which is specific and does not introduce the main topic. Paragraph 3 starts with 'The introduction,' which also does not stand alone. Paragraph 4 starts with 'As a result,' which shows it is dependent on previous information.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the text by showing the results of the changes in storage. It uses the phrase 'As a result,' which signals a conclusion. This follows the Conclusive Words rule.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it gives specific examples of early storage methods. This follows the Broader to Specific Strategy. The first paragraph talks about the evolution, and the second paragraph explains what early computers used.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it shows the next step in storage technology. This follows the Logical Order rule. The second paragraph talks about old methods, and the third paragraph explains the new methods.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it explains the impact of the advancements in storage. This follows the Cause and Effect Relationship rule. The third paragraph talks about new storage methods, and the fourth paragraph explains how these methods help us today.