| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] not been able [verb] | 88 |
|
| 2 | [vb past] not been [verb] [noun] | 24 |
|
| 3 | [vb past] been able [verb] [noun] | 20 |
|
| 4 | not been able [verb] [noun] | 15 |
|
