| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] it is necessary [prep] | 10 |
|
| 2 | [verb] it is necessary for | 5 |
|
| 3 | [to-vb] it is necessary [prep] | 5 |
|
| 4 | [verb] it is necessary for | 5 |
|
