- Authors, American--19th century--Biography (1)
- Civil disobedience (1)
- English language--Grammar, Generative (1)
- English language--Study and teaching (1)
- Generative grammar (1)
- Metaphor (1)
- Natural history--Massachusetts--Walden Woods (1)
- Solitude (1)
- Thoreau, Henry David, 1817-1862. Walden (1)
- Thoreau, Henry David, 1817-1862.--Civil disobedience (1)
- Walden Woods (Mass.)--Social life and customs (1)
- Wilderness areas--Massachusetts--Walden Woods (1)
- 比喩 (1)