| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it [vb mod] have been | 3673 |
|
| 2 | it would have been | 1414 |
|
| 3 | it must have been | 781 |
|
| 4 | it could have been | 502 |
|
| 5 | it might have been | 450 |
|
| 6 | it may have been | 321 |
|
| 7 | it should have been | 230 |
|
| 8 | it [vb mod] 've been | 90 |
|
| 9 | it will have been | 44 |
|
| 10 | it 'd have been | 10 |
|
| 11 | it [vb mod] to have been | 8 |
|
| 12 | it ought have been | 8 |
|
| 13 | it need have been | 5 |
|
