| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [verb] been in | 467 |
|
| 2 | must [verb] been [prep] | 294 |
|
| 3 | must [verb] be in | 90 |
|
| 4 | must [verb] [be] in | 90 |
|
| 5 | must [verb] [been] in | 89 |
|
