| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] over a period [prep] weeks | 5 |
|
| 2 | [adv] over a period of week | 5 |
|
| 3 | [adv] over a period of week | 5 |
|
| 4 | [adv] over a period [prep] week | 5 |
|
