| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [verb] | 783 |
|
| 2 | [modal v] have been put | 70 |
|
| 3 | must have [be] put | 5 |
|
| 4 | must have be put | 5 |
|
| 5 | must have been put | 5 |
|
| 6 | must [vb infin] been put | 5 |
|
| 7 | must have [been] put | 5 |
|
| 8 | must [verb] been put | 5 |
|
