| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [be] [verb] that | 641 |
|
| 2 | must [be] [vb pp] that | 626 |
|
| 3 | [modal v] [be] observed that | 40 |
|
| 4 | [vb mod] [be] observed that | 40 |
|
| 5 | must [be] observed [conj] | 11 |
|
| 6 | must [be] observed that | 9 |
|
| 7 | must [be] observe that | 9 |
|
| 8 | must [be] observed that | 9 |
|
