| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | where it is necessary [verb] | 19 |
|
| 2 | where it [is] necessary [verb] | 19 |
|
| 3 | where it [is] necessary [verb] | 19 |
|
| 4 | where it [is] necessary [to-vb] | 19 |
|
