| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over [art] [adj -er] period | 57 |
|
| 2 | over a [adj -er] period | 56 |
|
| 3 | over a [adj -er] period | 56 |
|
| 4 | over [art] longer period | 52 |
|
