| very | 20 | degree |
| because of its natural formation in layers | 6 | cause |
| exceptionally | 3 | degree |
| slate → be → hard | 34 |
| slate → be → tough | 9 |
| slate → be → difficult | 5 |
| slate → be → harder | 4 |
| negative | neutral | positive |
| 0.287 | 0.469 | 0.245 |
| Raw frequency | 52 |
| Normalized frequency | 0.702 |
| Modifier score | 0.500 |
| Perplexity | 202.160 |