| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could have be [vb pp] | 1042 |
|
| 2 | could be [vb pp] for | 644 |
|
| 3 | have be [vb pp] for | 285 |
|
| 4 | could have [vb pp] for | 87 |
|
