| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [det] [noun] | 49 |
|
| 2 | must have been [det] [noun sg] | 34 |
|
| 3 | must have been some [noun] | 34 |
|
| 4 | must have been [det] [noun pl] | 13 |
|
| 5 | must have been many [noun] | 7 |
|
| 6 | must have been [det] sort | 6 |
|
| 7 | must have been [det] sort | 6 |
|
