| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it [be] difficult for him [to-vb] | 10 |
|
| 2 | it be difficult for him [verb] | 10 |
|
| 3 | it was difficult for him [verb] | 6 |
|
| 4 | it [was/were] difficult for him [verb] | 6 |
|
