| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it be difficult [prep] i | 20 |
|
| 2 | it be [prep] i [to-vb] | 18 |
|
| 3 | be difficult [prep] i [to-vb] | 16 |
|
| 4 | it difficult [prep] i [to-vb] | 6 |
|
