| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | they could [adv] have [vb pp] [prep] | 13 |
|
| 2 | they could [adv] have [verb] [prep] | 13 |
|
| 3 | they could [adv] have [verb] [prep] | 13 |
|
| 4 | they could [adv] have [verb] [prep] | 12 |
|
