| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [vb infin] [adv] | 7332 |
|
| 2 | [vb mod] [vb infin] [not/n't] | 743 |
|
| 3 | [modal v] [vb infin] [not/n't] | 743 |
|
| 4 | could [verb] [not/n't] | 55 |
|
| 5 | could [vb infin] [not/n't] | 54 |
|
