| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [is] [adj] [prep] we [to-vb] | 108 |
|
| 2 | [is] difficult [prep] [pron] [to-vb] | 58 |
|
| 3 | [be] difficult [prep] we [to-vb] | 24 |
|
| 4 | [is] difficult [prep] we [verb] | 17 |
|
