| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [Wh det] [pers pn] [is] difficult [to-vb] | 22 |
|
| 2 | [Wh det] it [is] difficult [verb] | 22 |
|
| 3 | which [pers pn] [is] difficult [verb] | 22 |
|
| 4 | [Wh det] [pers pn] is difficult [verb] | 21 |
|
