| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | which have been [v-ing] on | 23 |
|
| 2 | which have be [v-ing] on | 23 |
|
| 3 | which have be going on | 20 |
|
| 4 | which had be [v-ing] on | 10 |
|
| 5 | which has be [v-ing] on | 9 |
|
