| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] must [be] [vb pp] prior | 6 |
|
| 2 | must [be] [vb pp] prior [prep] | 9 |
|
| 3 | must [be] [vb pp] prior [prep] | 9 |
|
| 4 | must [be] [vb pp] prior to | 9 |
|
| 5 | must [be] [vb pp] prior to | 9 |
|
