| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] what happened at | 27 |
|
| 2 | [prep] [Wh det] happened at | 27 |
|
| 3 | [prep] [pron] happened at | 27 |
|
| 4 | [prep] what happened at | 27 |
|
| 5 | of [pron] happened at | 8 |
|
| 6 | about [pron] happened at | 8 |
|
