| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] n't [verb] [conj] [pron] [verb] | 446 |
|
| 2 | could [adv] [verb] [conj] [pron] [verb] | 199 |
|
| 3 | could not [verb] [conj] [pron] [verb] | 137 |
|
| 4 | could [not/n't] [verb] [conj] [pron] [verb] | 137 |
|
