| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [not/n't] have been possible for | 7 |
|
| 2 | [not/n't] [verb] been possible for | 7 |
|
| 3 | [not/n't] [vb infin] been possible for | 7 |
|
| 4 | [not/n't] have been possible for | 7 |
|
| 5 | not [verb] been possible for | 7 |
|
