| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] been [prep] a [noun] | 482 |
|
| 2 | must [verb] been a [noun] | 181 |
|
| 3 | must [verb] [prep] a [noun] | 129 |
|
| 4 | must [verb] been [prep] [noun] | 39 |
|
| 5 | must [verb] been [prep] a | 26 |
|
