| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb pp] to be necessary [to-vb] | 8 |
|
| 2 | [vb pp] to [be] necessary [to-vb] | 8 |
|
| 3 | [vb pp] to [be] necessary [to-vb] | 8 |
|
| 4 | [vb pp] to be necessary [to-vb] | 8 |
|
