| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [not/n't] necessary | 274 |
|
| 2 | it is necessary for | 104 |
|
| 3 | it is [not/n't] for | 102 |
|
| 4 | is [not/n't] necessary for | 58 |
|
