| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] [be] a | 15851 |
|
| 2 | [modal v] [be] a | 15851 |
|
| 3 | could [be] [art] | 2431 |
|
| 4 | could [be] [art] | 2431 |
|
| 5 | could [be] a | 1412 |
|
| 6 | could [be] a | 1215 |
|
