| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is [adj] [conj] necessary | 22 |
|
| 2 | is [adj] [conj] necessary | 21 |
|
| 3 | is [vb pp] [conj] necessary | 17 |
|
| 4 | is [verb] [conj] necessary | 17 |
|
