| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [adj] year ['s] [noun] [prep] | 405 |
|
| 2 | [prep] [num] year ['s] [noun] [prep] | 195 |
|
| 3 | [prep] 20 [noun] ['s] [noun] [prep] | 13 |
|
| 4 | [prep] 20 year ['s] [noun] [prep] | 12 |
|
| 5 | [prep] 20 year [unc] [noun] [prep] | 12 |
|
| 6 | [prep] 20 year ['s] [noun] [prep] | 12 |
|
