| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could n't [verb] a | 535 |
|
| 2 | could n't have [verb] | 469 |
|
| 3 | could have [verb] a | 318 |
|
| 4 | n't have [verb] a | 204 |
|
| 5 | could n't have a | 28 |
|
