| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | was [v-ing] [prep] | 19633 |
|
| 2 | was [verb] at | 6692 |
|
| 3 | be [v-ing] at | 6347 |
|
| 4 | [be] [v-ing] at | 6347 |
|
| 5 | [was/were] [v-ing] at | 2698 |
|
