| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] could [not/n't] have | 1047 |
|
| 2 | [adv] [pron] could [not/n't] | 953 |
|
| 3 | [adv] [pron] could have | 482 |
|
| 4 | [adv] could [not/n't] have | 58 |
|
