| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it be [adj] [prep] us [verb] | 122 |
|
| 2 | it be necessary [prep] [pron] [verb] | 48 |
|
| 3 | it be necessary [prep] [pers pn] [verb] | 44 |
|
| 4 | it be necessary [prep] we [verb] | 11 |
|
| 5 | it [be] necessary [prep] us [verb] | 11 |
|
| 6 | [pron] be necessary [prep] us [verb] | 11 |
|
