| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] have been for | 6 |
|
| 2 | could [adv] have been for | 6 |
|
| 3 | could [adv] have been for | 6 |
|
| 4 | could not have been for | 5 |
|
| 5 | could [not/n't] have been for | 5 |
|
