| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is not [adv] necessary [verb] | 20 |
|
| 2 | is not [adv] necessary [verb] | 20 |
|
| 3 | is not [adv] necessary [to-vb] | 20 |
|
| 4 | is not always necessary [verb] | 9 |
|
| 5 | is not always necessary [verb] | 9 |
|
