| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] over [num] years | 638 |
|
| 2 | [prep] over [adj] years | 638 |
|
| 3 | [prep] [adv] 30 years | 104 |
|
| 4 | [prep] [adv] 30 years | 104 |
|
| 5 | [prep] over 30 [noun] | 68 |
|
| 6 | [prep] over 30 [noun pl] | 62 |
|
| 7 | [prep] over 30 year | 53 |
|
| 8 | [prep] over 30 years | 53 |
|
| 9 | [prep] over 30 years | 53 |
|
