| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [vb infin] [to-vb] | 1359 |
|
| 2 | [vb infin] [to-vb] [noun prp] | 1148 |
|
| 3 | could [vb infin] [noun prp] | 1088 |
|
| 4 | could [to-vb] [noun prp] | 18 |
|
