| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [verb] been [verb] [verb] | 489 |
|
| 2 | could [verb] be [verb] [verb] | 81 |
|
| 3 | could [verb] [be] [verb] [verb] | 81 |
|
| 4 | could [verb] [been] [verb] [verb] | 79 |
|
