| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] have been [v-ing] [art] [noun sg] | 60 |
|
| 2 | must have been [v-ing] [art] [noun] | 14 |
|
| 3 | must have been [verb] [art] [noun sg] | 14 |
|
| 4 | must have [been] [v-ing] [art] [noun sg] | 11 |
|
| 5 | must have be [v-ing] [art] [noun sg] | 11 |
|
| 6 | must have [be] [v-ing] [art] [noun sg] | 11 |
|
| 7 | must [verb] been [v-ing] [art] [noun sg] | 11 |
|
