| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which [vb -s] back [prep] the | 32 |
|
| 2 | [Wh det] [vb -s] back to the | 29 |
|
| 3 | [Wh det] dates back [prep] the | 14 |
|
| 4 | [Wh det] goes back [prep] the | 8 |
|
