| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | they could [verb] | 4234 |
|
| 2 | they could [vb infin] | 4177 |
|
| 3 | [pron] could buy | 196 |
|
| 4 | [pers pn] could buy | 183 |
|
| 5 | they [modal v] buy | 89 |
|
| 6 | they could buy | 24 |
|
| 7 | they could buy | 24 |
|
