| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] which [verb] [prep] | 799 |
|
| 2 | [prep] [verb] back [prep] | 546 |
|
| 3 | which [verb] back [prep] | 152 |
|
| 4 | [prep] which [verb] back | 23 |
|
