| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] it [is] difficult [to-vb] | 428 |
|
| 2 | it [is] difficult [to-vb] [noun pl] | 54 |
|
| 3 | [conj] it [is] [to-vb] [noun pl] | 10 |
|
