| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] over a period | 83 |
|
| 2 | over a [adj -er] period | 56 |
|
| 3 | [verb] over a [adj -er] | 26 |
|
| 4 | [verb] a [adj -er] period | 21 |
|
