| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [not/n't] [verb] | 21358 |
|
| 2 | [not/n't] [verb] [vb pp] | 6408 |
|
| 3 | could [verb] [vb pp] | 5483 |
|
| 4 | could [not/n't] [vb pp] | 5 |
|
