| to allow mandrel | 8 | purpose |
| after spreading two adjacent vertebrae | 6 | temporal |
| by a surgeon | 3 | other |
| bore → be → deep | 10 |
| bore → be made → deep | 4 |
| negative | neutral | positive |
| 0.028 | 0.839 | 0.132 |
| Raw frequency | 14 |
| Normalized frequency | 0.446 |
| Modifier score | 0.500 |
| Perplexity | 406.247 |