| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | was [v-ing] when it [vb past] | 6 |
|
| 2 | [was/were] [v-ing] when it [vb past] | 6 |
|
| 3 | be [v-ing] when it [vb past] | 6 |
|
| 4 | [be] [v-ing] when it [vb past] | 6 |
|
