| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | as far back as [num] [adv] | 7 |
|
| 2 | as far back as [num] [Wh adv] | 5 |
|
| 3 | as far back as [num] when | 5 |
|
| 4 | as far back as [num] when | 5 |
|
