| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] over a period | 311 |
|
| 2 | [noun] [conj] over a | 51 |
|
| 3 | [conj] over a period | 29 |
|
| 4 | [noun] [conj] a period | 20 |
|
