| biologically | 12 | manner |
| from water | 9 | other |
| from rotten waste | 9 | other |
| methane → be → produced | 158 |
| methane → be → generated | 26 |
| methane → be → formed | 25 |
| methane → be → created | 19 |
| methane → be → made | 4 |
| negative | neutral | positive |
| 0.306 | 0.605 | 0.090 |
| Raw frequency | 232 |
| Normalized frequency | 0.922 |
| Modifier score | 0.600 |
| Perplexity | 79.833 |