| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have [been] [verb] [det] | 1496 |
|
| 2 | must have [been] [verb] | 793 |
|
| 3 | must have [verb] [det] | 264 |
|
| 4 | must have [been] [det] | 93 |
|
