A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of the text. It talks about a problem, which is the shortage of scholars in new energy. This is a broad overview of the issue. Why other lines are not chosen? Paragraph 2 is not chosen because it starts with 'Especially,' which is a conjunction. Paragraph 3 is not chosen because it starts with 'With,' which is also a conjunction. Paragraph 4 is not chosen because it starts with 'Become,' which is not a general statement.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the ideas in the text. It talks about the benefits of becoming an engineer, which is the conclusion of the discussion about the shortage of scholars and the funding for energy research.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it talks about a specific group, engineers, related to the shortage mentioned in Paragraph 1. This shows a logical order from a general problem to a specific group affected.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it talks about the money for energy research, which is important for engineers. This shows a logical order from the specific group of engineers to the broader topic of funding.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it explains the benefits of the increased funding for engineers. This shows a logical order from the funding to the opportunities for engineers.