| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | over a long period of [noun] | 75 |
|
| 2 | over a long period of [noun sg] | 72 |
|
| 3 | over a long period of time | 71 |
|
| 4 | over a long period of time | 71 |
|
| 5 | [noun] over a long period of | 40 |
|
| 6 | [noun sg] over a long period of | 32 |
|
| 7 | [verb] over a long period of | 13 |
|
| 8 | [vb pp] over a long period of | 12 |
|
| 9 | [adv] over a long period of | 8 |
|
| 10 | [noun pl] over a long period of | 7 |
|
| 11 | [adv] over a long period of | 7 |
|
