| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] be [v-ing] [adj] | 1405 |
|
| 2 | must be [verb] [adj] | 418 |
|
| 3 | must be [v-ing] [adj] | 88 |
|
| 4 | must [be] [v-ing] [adj] | 88 |
|
| 5 | must [be] [v-ing] [adj] | 88 |
|
