| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | what have been happen [prep] | 55 |
|
| 2 | [Wh det] have been happening [prep] | 55 |
|
| 3 | [Wh det] has been happen [prep] | 28 |
|
| 4 | [Wh det] have been happen in | 24 |
|
| 5 | [Wh det] 's been happen [prep] | 20 |
|
| 6 | [Wh det] have been happen to | 14 |
|
| 7 | [Wh det] had been happen [prep] | 7 |
|
