| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] i could | 535 |
|
| 2 | [vb past] [vb pp] i | 194 |
|
| 3 | [vb pp] i could | 39 |
|
| 4 | [vb past] [vb pp] could | 15 |
|
