| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it be difficult [to-vb] [adj] | 245 |
|
| 2 | it be [adj] [to-vb] these | 107 |
|
| 3 | it [be] difficult [to-vb] these | 17 |
|
| 4 | [pron] be difficult [to-vb] these | 17 |
|
| 5 | it be difficult [verb] these | 17 |
|
