| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have been [v-ing] [prep] a | 521 |
|
| 2 | it have been [v-ing] [prep] | 131 |
|
| 3 | it have been [prep] a | 35 |
|
| 4 | it have been [v-ing] a | 11 |
|
