| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [verb] been [adj] | 761 |
|
| 2 | [Wh det] [verb] been [adj] | 385 |
|
| 3 | [Wh det] must [verb] been | 120 |
|
| 4 | [Wh det] must [verb] [adj] | 41 |
|
