| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is necessary [verb] that | 51 |
|
| 2 | is necessary [to-vb] that | 50 |
|
| 3 | is necessary ensure that | 16 |
|
| 4 | is necessary to ensure that | 15 |
|
| 5 | is necessary to show that | 7 |
|
| 6 | is necessary show that | 7 |
|
