| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | after [adj] years | 1853 |
|
| 2 | after [num] years | 1681 |
|
| 3 | [prep] 20 years | 501 |
|
| 4 | after 20 [noun] | 95 |
|
| 5 | after 20 [noun pl] | 91 |
|
| 6 | after 20 years | 52 |
|
| 7 | after 20 year | 52 |
|
