| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could be [vb pp] [to-vb] [prep] [noun sg] | 19 |
|
| 2 | could be [verb] [to-vb] [prep] [noun sg] | 19 |
|
| 3 | could be [verb] [to-vb] [prep] [noun sg] | 19 |
|
