| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [adv] a year | 355 |
|
| 2 | [adv] [prep] [adv] a | 310 |
|
| 3 | [adv] [adv] a year | 278 |
|
| 4 | [adv] [prep] a year | 113 |
|
