| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been [v-ing] [prep] a | 521 |
|
| 2 | who have been [v-ing] [prep] | 332 |
|
| 3 | who have been [prep] a | 43 |
|
| 4 | who have been [v-ing] a | 34 |
|
