| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could n't [verb] | 12359 |
|
| 2 | [modal v] n't remember | 1534 |
|
| 3 | could [adv] remember | 444 |
|
| 4 | could [not/n't] remember | 349 |
|
| 5 | could not remember | 349 |
|
