| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | when [noun prp] [verb] [adv] [prep] | 265 |
|
| 2 | [conj] [noun prp] [verb] back [prep] | 243 |
|
| 3 | when [noun] [verb] back [prep] | 72 |
|
| 4 | when [noun prp] [verb] back [prep] | 63 |
|
