| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a [adj] days | 826 |
|
| 2 | back [prep] a [adj] | 574 |
|
| 3 | back [prep] [adj] days | 40 |
|
| 4 | back a [adj] days | 5 |
|
