| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [vb infin] [to-vb] [prep] | 165 |
|
| 2 | could [vb infin] be [prep] | 114 |
|
| 3 | could [vb infin] be [to-vb] | 49 |
|
| 4 | [vb infin] be [to-vb] [prep] | 48 |
|
| 5 | could be [to-vb] [prep] | 7 |
|
