| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] be necessary [to-vb] [prep] | 60 |
|
| 2 | be necessary [to-vb] [pron] [prep] | 46 |
|
| 3 | [vb mod] be necessary [to-vb] [pron] | 38 |
|
| 4 | [vb mod] be [to-vb] [pron] [prep] | 37 |
|
