| permanently | 4 | manner |
| to the rail | 3 | location |
| securely | 2 | manner |
| rail → be → attached | 32 |
| rail → be → fastened | 5 |
| rail → be attached to → structure | 3 |
| rail → be fastened to → the structure | 3 |
| negative | neutral | positive |
| 0.130 | 0.784 | 0.085 |
| Raw frequency | 43 |
| Normalized frequency | 0.712 |
| Modifier score | 0.933 |
| Perplexity | 368.839 |