| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [be] [prep] [be] | 9 |
|
| 2 | must [be] [prep] be | 9 |
|
| 3 | must be [prep] [be] | 9 |
|
| 4 | must [be] to [be] | 9 |
|
| 5 | must [be] to [be] | 9 |
|
