| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [verb] it is necessary | 60 |
|
| 2 | [vb base] it [is] necessary | 34 |
|
| 3 | [verb] it 's necessary | 33 |
|
| 4 | think it [is] necessary | 31 |
|
| 5 | [vb infin] it [is] necessary | 26 |
|
| 6 | think it [is] necessary | 16 |
|
| 7 | think it [is] necessary | 14 |
|
| 8 | [vb -s] it [is] necessary | 13 |
|
| 9 | feel it [is] necessary | 12 |
|
| 10 | [vb pp] it [is] necessary | 11 |
|
| 11 | [to-vb] it [is] necessary | 7 |
|
| 12 | feel it [is] necessary | 6 |
|
| 13 | believe it [is] necessary | 6 |
|
