| # | Download | Text | Text Size |
|---|---|---|---|
| 1 | | Acquiring knowledge.pdf | 31k |
| 2 | | Astronomy, from 50 thousand years ago to 5 thousand years ago.pdf | 154k |
| 3 | | Chem, Stoichiometry.pdf | 35k |
| 4 | | Four good behaviors.pdf | 27k |
| 5 | | Happiness chirping.pdf | 40k |
| 6 | | Know that.pdf | 19k |
| 7 | | Limp donkey with leopard skin.pdf | 24k |
| 8 | | Write down to memorize.pdf | 29k |