| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [be] [vb pp] [prep] [verb] | 3446 |
|
| 2 | could [be] [verb] [prep] [verb] | 454 |
|
| 3 | could [be] [vb pp] [prep] [verb] | 450 |
|
