1. as a clue, runs through the whole article.
2. Point out the main idea of the article
3. The starting point of the author's emotion
4. figurative meaning, symbolic meaning
5. Point out the main characters or events.
6. Puns (surface and deep)
7. Attract readers and stimulate their interest in reading.
The answer is as follows:
1. Mulan's poem named the central figure of the article, and the whole text revolves around Mulan's experience.
2. As a clue running through the whole text, the whole text revolves around the main story of Mulan joining the army as her father.