| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] years [unc] [noun] | 22 |
|
| 2 | 30 years [unc] [noun] | 17 |
|
| 3 | [prep] 30 years [unc] | 11 |
|
| 4 | [prep] 30 [unc] [noun] | 8 |
|
| 5 | [prep] 30 years [noun] | 7 |
|
