| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [Wh det] could be [vb pp] [prep] | 589 |
|
| 2 | could be [vb pp] [prep] [be] | 166 |
|
| 3 | [Wh det] could be [vb pp] [be] | 8 |
|
