| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [v-ing] when they [vb past] | 20 |
|
| 2 | be [v-ing] when they [vb past] | 20 |
|
| 3 | [was/were] [v-ing] when they [vb past] | 16 |
|
| 4 | was [v-ing] when they [vb past] | 10 |
|
| 5 | were [v-ing] when they [vb past] | 6 |
|
