| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] [is] difficult [prep] us [verb] | 15 |
|
| 2 | [pers pn] [is] difficult [prep] us [verb] | 15 |
|
| 3 | [pron] [is] difficult for us [verb] | 15 |
|
| 4 | it [is] difficult [prep] us [verb] | 15 |
|
| 5 | it [is] difficult [prep] us [verb] | 15 |
|
| 6 | [pron] [is] difficult [prep] us [to-vb] | 15 |
|
| 7 | [pron] is difficult [prep] us [verb] | 12 |
|
