| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] have been [adj] | 178 |
|
| 2 | [adv] have been [prep] [adj] | 81 |
|
| 3 | could [adv] have been [prep] | 34 |
|
| 4 | could have been [prep] [adj] | 30 |
|
