| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] over a period [prep] | 295 |
|
| 2 | [noun] over a period of | 289 |
|
| 3 | [noun] over a period of | 289 |
|
| 4 | [noun sg] over a period [prep] | 168 |
|
| 5 | [noun pl] over a period [prep] | 105 |
|
| 6 | [noun prp] over a period [prep] | 12 |
|
| 7 | [n mass] over a period [prep] | 9 |
|
| 8 | place over a period [prep] | 9 |
|
| 9 | place over a period [prep] | 8 |
|
