| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] have been clear | 14 |
|
| 2 | [vb mod] have been clear | 14 |
|
| 3 | must have been clear | 7 |
|
| 4 | would have been clear | 7 |
|
| 5 | would have been clear | 7 |
|
| 6 | must have been clear | 7 |
|
