| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be difficult [prep] [pron] [to-vb] | 117 |
|
| 2 | it be difficult [prep] [pron] | 102 |
|
| 3 | it be [prep] [pron] [to-vb] | 98 |
|
| 4 | it difficult [prep] [pron] [to-vb] | 65 |
|
