| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | this has been [v-ing] on for | 6 |
|
| 2 | this has been [verb] on for | 6 |
|
| 3 | this has been go on for | 6 |
|
| 4 | this has been going on for | 6 |
|
