| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [verb] at a | 2102 |
|
| 2 | could [be] [verb] at | 263 |
|
| 3 | could [be] [verb] a | 134 |
|
| 4 | could [verb] at a | 27 |
|
