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