| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] 1989 when [pers pn] | 11 |
|
| 2 | [prep] 1989 [Wh adv] [pers pn] | 11 |
|
| 3 | in 1989 [Wh adv] [pers pn] | 7 |
|
| 4 | [prep] 1989 [Wh adv] he | 7 |
|
