| for every household | 6 | transitive-object |
| to draw blood | 3 | purpose |
| to produce these higher grades | 3 | purpose |
| vacuum → be → required | 24 |
| vacuum → be → necessary | 10 |
| vacuum → be → must | 5 |
| vacuum → be → necessity | 3 |
| negative | neutral | positive |
| 0.134 | 0.679 | 0.187 |
| Raw frequency | 42 |
| Normalized frequency | 0.574 |
| Modifier score | 0.000 |
| Perplexity | 431.820 |