| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | not [been] able [verb] | 266 |
|
| 2 | [been] able [verb] a | 161 |
|
| 3 | not [been] [verb] a | 32 |
|
| 4 | not able [verb] a | 13 |
|
