| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has [been] [adj] for | 302 |
|
| 2 | have [been] necessary for | 25 |
|
| 3 | [verb] [been] necessary for | 25 |
|
| 4 | has [been] necessary [prep] | 11 |
|
| 5 | has [been] necessary [prep] | 11 |
|
| 6 | has [be] necessary for | 6 |
|
| 7 | has [been] necessary for | 6 |
|
| 8 | [vb -s] [been] necessary for | 6 |
|
