| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [v-ing] [Wh det] have happened to [pron] | 8 |
|
| 2 | [v-ing] what have [vb pp] to [pron] | 8 |
|
| 3 | [v-ing] [Wh det] have [vb pp] to [pers pn] | 7 |
|
| 4 | [v-ing] [Wh det] had [vb pp] to [pron] | 6 |
|
