| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | when it [be] [verb] | 1501 |
|
| 2 | when it [be] [v-ing] | 144 |
|
| 3 | [conj] it [be] operating | 12 |
|
| 4 | when [pron] [be] operating | 8 |
|
| 5 | [subord] it [be] operating | 8 |
|
| 6 | when it [be] operate | 6 |
|
| 7 | when it [be] operating | 5 |
|
