| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] back [prep] [art] [adj] period | 11 |
|
| 2 | [verb] back [prep] [art] [adj] period | 8 |
|
| 3 | [verb] back [prep] [art] period [prep] | 5 |
|
| 4 | [verb] back [prep] [art] period [prep] | 5 |
|
