| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [prep] be | 149 |
|
| 2 | must [prep] [be] | 149 |
|
| 3 | must [prep] [be] | 149 |
|
| 4 | must of [be] | 147 |
|
| 5 | must [prep] [been] | 147 |
|
| 6 | must of [be] | 147 |
|
| 7 | must [prep] been | 147 |
|
