| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a [adj] period [prep] | 173 |
|
| 2 | [vb pp] over a [adj] period | 72 |
|
| 3 | [vb pp] over a period [prep] | 71 |
|
| 4 | [vb pp] a [adj] period [prep] | 20 |
|
