| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] over a period [prep] | 76 |
|
| 2 | [verb] over a period of | 75 |
|
| 3 | [verb] over a period of | 75 |
|
| 4 | [vb pp] over a period [prep] | 71 |
|
| 5 | make over a period [prep] | 5 |
|
| 6 | made over a period [prep] | 5 |
|
