| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [subord] it had been [adj] | 70 |
|
| 2 | if it [vb past] been [adj] | 46 |
|
| 3 | [subord] it [vb past] been possible | 11 |
|
| 4 | [subord] it [vb past] been necessary | 6 |
|
