| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [adv] a year | 355 |
|
| 2 | [vb past] [prep] [adv] a | 211 |
|
| 3 | [vb past] [adv] a year | 51 |
|
| 4 | [vb past] [prep] a year | 50 |
|
