| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] have [verb] [pron] | 9786 |
|
| 2 | could [verb] [verb] [pron] | 1639 |
|
| 3 | could [vb infin] [verb] [pron] | 1638 |
|
| 4 | could have [verb] [pron] | 1288 |
|
