| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [be] [prep] | 1101 |
|
| 2 | must [prep] [be] | 149 |
|
| 3 | [be] [prep] [be] | 71 |
|
| 4 | must [be] [be] | 8 |
|
