| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb past] [verb] back as | 11 |
|
| 2 | [verb] [to-vb] back as | 9 |
|
| 3 | have [verb] back as | 6 |
|
| 4 | had [verb] back as | 5 |
|
