| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which have occurred [prep] the | 32 |
|
| 2 | [Wh det] have occurred in the | 25 |
|
| 3 | [Wh det] have occurred [prep] the | 16 |
|
| 4 | [Wh det] has occurred [prep] the | 14 |
|
| 5 | [Wh det] had occurred [prep] the | 12 |
|
| 6 | what have occurred [prep] the | 10 |
|
| 7 | [Wh det] have occurred during the | 6 |
|
