| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a [adj] period | 519 |
|
| 2 | a [adj] period [conj] | 159 |
|
| 3 | over a [adj] [conj] | 19 |
|
| 4 | over [adj] period [conj] | 9 |
|
| 5 | over a period [conj] | 6 |
|
