| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | had been [v-ing] on [art] | 90 |
|
| 2 | they had been [v-ing] [art] | 29 |
|
| 3 | they had been on [art] | 16 |
|
| 4 | they had been [v-ing] on | 10 |
|
