| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [v-ing] back [prep] [art] | 1550 |
|
| 2 | [v-ing] back [prep] [art] | 1550 |
|
| 3 | [v-ing] [adv] [prep] an | 463 |
|
| 4 | [v-ing] back [prep] a | 182 |
|
| 5 | [verb] back [prep] an | 146 |
|
| 6 | [v-ing] back [prep] an | 29 |
|
