| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been [vb pp] about by | 31 |
|
| 2 | have been bring about by | 31 |
|
| 3 | have been brought about by | 31 |
|
| 4 | has been [verb] about by | 16 |
|
| 5 | have been [verb] about by | 7 |
|
