| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [was/were] not [v-ing] | 1858 |
|
| 2 | [was/were] [v-ing] back | 499 |
|
| 3 | not [v-ing] back | 147 |
|
| 4 | [was/were] not back | 5 |
|
