| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [art] [adj -est] | 14 |
|
| 2 | must [vb infin] been [art] [adj -est] | 14 |
|
| 3 | must have been [art] [adj -est] | 14 |
|
| 4 | must [verb] been the [adj -est] | 14 |
|
