| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [vb infin] [noun] | 5118 |
|
| 2 | could [vb infin] only | 243 |
|
| 3 | [vb infin] only [noun] | 131 |
|
| 4 | could only [noun] | 9 |
|
