| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [det] | 92 |
|
| 2 | must have [been] some | 42 |
|
| 3 | must have [been] many | 20 |
|
| 4 | must have [been] those | 5 |
|
| 5 | must have [been] several | 5 |
|
