| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [verb] [to-vb] | 1341 |
|
| 2 | it is often [verb] | 364 |
|
| 3 | is often [verb] [to-vb] | 105 |
|
| 4 | it often [verb] [to-vb] | 12 |
|
