| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it must have been [prep] | 82 |
|
| 2 | it must have been [prep] | 82 |
|
| 3 | it [vb mod] have been for | 14 |
|
| 4 | it [modal v] have been for | 14 |
|
| 5 | [pron] must have been for | 8 |
|
| 6 | it must have been for | 6 |
|
| 7 | it must [verb] been for | 6 |
|
| 8 | it must have been for | 6 |
|
| 9 | it must have [been] for | 6 |
|
| 10 | it must have been for | 6 |
|
| 11 | it must have been for | 6 |
|
| 12 | [pers pn] must have been for | 6 |
|
| 13 | it must [vb infin] been for | 6 |
|
| 14 | it must have [be] for | 6 |
|
| 15 | it must have be for | 6 |
|
