| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] is necessary [to-vb] | 1085 |
|
| 2 | [vb infin] [pron] necessary [to-vb] | 70 |
|
| 3 | [vb infin] [pron] is necessary | 18 |
|
| 4 | [vb infin] [pron] is [to-vb] | 17 |
|
