| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] [verb] [prep] their [noun] | 8 |
|
| 2 | could [adv] [vb infin] [prep] their [noun] | 8 |
|
| 3 | could [adv] [verb] [prep] their [noun sg] | 5 |
|
