| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it [is] difficult [to-vb] [noun pl] | 54 |
|
| 2 | it is difficult [to-vb] [noun pl] | 44 |
|
| 3 | it 's difficult [to-vb] [noun pl] | 10 |
|
| 4 | it [is] difficult to find [noun pl] | 6 |
|
| 5 | it [is] difficult to make [noun pl] | 5 |
|
