| for students | 9 | transitive-object |
| to the educational experience | 7 | purpose |
| for the assignment | 6 | purpose |
| textbook → be → essential | 32 |
| textbook → be → essential reading | 16 |
| textbook → be → important | 13 |
| textbook → be → vital | 4 |
| textbook → be → essential resource | 4 |
| textbook → be of → great importance | 3 |
| negative | neutral | positive |
| 0.053 | 0.384 | 0.564 |
| Raw frequency | 72 |
| Normalized frequency | 0.666 |
| Modifier score | 0.400 |
| Perplexity | 141.770 |