| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have be [noun] [prep] [noun] | 7 |
|
| 2 | must have [been] [noun] [prep] [noun] | 7 |
|
| 3 | must have [be] [noun] [prep] [noun] | 7 |
|
| 4 | must have been [noun] [prep] [noun] | 7 |
|
| 5 | must have [be] [noun] [prep] [noun sg] | 5 |
|
