| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it has [been] [adj] for | 52 |
|
| 2 | it [verb] [been] necessary for | 9 |
|
| 3 | it have [been] necessary for | 9 |
|
| 4 | it has [been] necessary [prep] | 8 |
|
| 5 | it has [been] necessary [prep] | 8 |
|
| 6 | it has [been] necessary for | 5 |
|
| 7 | [pron] has [been] necessary for | 5 |
|
| 8 | it has [been] necessary for | 5 |
|
| 9 | [pers pn] has [been] necessary for | 5 |
|
| 10 | it has [be] necessary for | 5 |
|
| 11 | it [vb -s] [been] necessary for | 5 |
|
