| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over [art] period of | 684 |
|
| 2 | over a period [prep] | 628 |
|
| 3 | over the period [prep] | 109 |
|
| 4 | over [art] period from | 16 |
|
| 5 | over [art] period to | 8 |
|
| 6 | over [art] period in | 7 |
|
| 7 | over [art] period since | 6 |
|
