| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it must [verb] [be] | 782 |
|
| 2 | must [verb] [be] at | 40 |
|
| 3 | it [verb] [be] at | 39 |
|
| 4 | it must [be] at | 14 |
|
| 5 | it must [verb] at | 11 |
|
