| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could be [vb pp] [vb mod] be | 10 |
|
| 2 | could be [vb pp] [modal v] be | 10 |
|
| 3 | could be [vb pp] would be | 8 |
|
| 4 | could be [vb pp] would be | 8 |
|
