| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [v-ing] [modal v] be | 522 |
|
| 2 | [verb] must be | 366 |
|
| 3 | [v-ing] must [be] | 33 |
|
| 4 | [v-ing] must [be] | 33 |
|
| 5 | [v-ing] must be | 33 |
|
