| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] back [prep] a time | 13 |
|
| 2 | back [prep] a [adj] time | 8 |
|
| 3 | back [prep] a [adj] time | 8 |
|
| 4 | back [prep] a long time | 5 |
|
| 5 | back [prep] a long time | 5 |
|
| 6 | back [prep] a time [adv] | 11 |
|
| 7 | back [prep] a time when | 10 |
|
| 8 | back [prep] a time when | 10 |
|
| 9 | back [prep] a time [Wh adv] | 10 |
|
