| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | who have [vb pp] back | 37 |
|
| 2 | [Wh pn] had [vb pp] back | 22 |
|
| 3 | [Wh pn] have come back | 15 |
|
| 4 | [Wh pn] has [vb pp] back | 5 |
|
