| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] over a [adj] period | 86 |
|
| 2 | [vb pp] over a [adj] period | 83 |
|
| 3 | [verb] [vb pp] over a [adj] | 35 |
|
| 4 | [verb] [vb pp] a [adj] period | 13 |
|
| 5 | [verb] [vb pp] over a period | 8 |
|
