| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] [be] necessary for | 184 |
|
| 2 | [noun] which [be] necessary | 82 |
|
| 3 | which [be] necessary for | 43 |
|
| 4 | [noun] which [be] for | 28 |
|
