| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which have been [verb] on for | 13 |
|
| 2 | which have been [v-ing] on for | 12 |
|
| 3 | which have been going on for | 10 |
|
| 4 | which have been go on for | 10 |
|
| 5 | which has been [verb] on for | 6 |
|
