| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it must [be] [vb pp] | 1391 |
|
| 2 | [vb pp] must [be] [vb pp] | 92 |
|
| 3 | [vb pp] it must [be] | 29 |
|
| 4 | [vb pp] it [be] [vb pp] | 19 |
|
