| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | who could have [be] [vb pp] [adv] | 5 |
|
| 2 | who could have [be] [vb pp] [adv prt] | 5 |
|
| 3 | who could have [been] [vb pp] [adv] | 5 |
|
| 4 | who could have been [vb pp] [adv] | 5 |
|
| 5 | who could have [be] [vb pp] [adv] | 5 |
|
| 6 | who could have be [vb pp] [adv] | 5 |
|
