| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a [adj] period | 519 |
|
| 2 | [adv prt] a [adj] period | 76 |
|
| 3 | [adv prt] over a [adj] | 55 |
|
| 4 | [adv prt] over a period | 29 |
|
