| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it [be] [prep] [be] | 1357 |
|
| 2 | it must [be] [prep] | 189 |
|
| 3 | it must [prep] [be] | 50 |
|
| 4 | must [be] [prep] [be] | 10 |
|
