| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could be [adv] | 2416 |
|
| 2 | [vb mod] be back | 975 |
|
| 3 | [modal v] be back | 975 |
|
| 4 | could [be] back | 43 |
|
| 5 | could be back | 43 |
|
| 6 | could be back | 43 |
|
| 7 | could [be] back | 43 |
|
