| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | necessary [to-vb] [det] [noun] [prep] | 81 |
|
| 2 | it necessary [to-vb] [det] [noun] | 19 |
|
| 3 | it necessary [to-vb] [noun] [prep] | 16 |
|
| 4 | it [to-vb] [det] [noun] [prep] | 15 |
|
