| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [modal v] [pers pn] have [verb] | 944 |
|
| 2 | could [pers pn] [verb] [verb] | 371 |
|
| 3 | could [pers pn] [vb infin] [verb] | 368 |
|
| 4 | could [pron] have [verb] | 285 |
|
| 5 | could [pers pn] have [verb] | 278 |
|
