| regularly | 6 | degree |
| to keep it | 5 | purpose |
| during this period | 4 | temporal |
| filter → need → cleaning | 42 |
| filter → require → cleaning | 32 |
| filter → need → washing | 5 |
| negative | neutral | positive |
| 0.360 | 0.553 | 0.086 |
| Raw frequency | 79 |
| Normalized frequency | 0.542 |
| Modifier score | 0.513 |
| Perplexity | 188.161 |