| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is necessary understand [det] statements | 5 |
|
| 2 | is necessary [verb] such statements | 5 |
|
| 3 | is necessary [to-vb] [det] statements | 5 |
|
| 4 | is necessary [verb] [det] statements | 5 |
|
| 5 | is necessary to understand [det] statements | 5 |
|
