| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | about what has [be] [v-ing] | 6 |
|
| 2 | about [Wh det] has [been] [v-ing] | 6 |
|
| 3 | about [Wh det] has be [v-ing] | 6 |
|
| 4 | about [Wh det] has been [v-ing] | 6 |
|
