| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [verb] [conj] | 4469 |
|
| 2 | it is difficult [verb] | 1529 |
|
| 3 | is difficult [verb] [conj] | 225 |
|
| 4 | it difficult [verb] [conj] | 79 |
|
| 5 | it is difficult [conj] | 22 |
|
