| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | what they [vb base] been [v-ing] | 19 |
|
| 2 | what they [vb base] [been] doing | 11 |
|
| 3 | what they 've [been] [v-ing] | 10 |
|
| 4 | what they have [been] [v-ing] | 9 |
|
