| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] have [vb pp] | 806 |
|
| 2 | [adv] have [vb pp] [noun pl] | 196 |
|
| 3 | could have [vb pp] [noun pl] | 75 |
|
| 4 | could [adv] have [noun pl] | 8 |
|
