| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] have [been] [prep] [adj] | 5 |
|
| 2 | could [adv] have [be] [prep] [adj] | 5 |
|
| 3 | could [adv] have been [prep] [adj] | 5 |
|
| 4 | could [adv] have be [prep] [adj] | 5 |
|
