| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] have | 1475 |
|
| 2 | [adv] have [noun sg] | 329 |
|
| 3 | could have [noun sg] | 92 |
|
| 4 | could [adv] [noun sg] | 41 |
|
