| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could have been [verb] [prep] [adj] | 39 |
|
| 2 | could have been [vb pp] [prep] [adj] | 38 |
|
| 3 | could have been [prep] [adj] [noun] | 8 |
|
| 4 | could have been [prep] [adj] [noun sg] | 6 |
|
