| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [is] [adv] [adj] [to-vb] | 10969 |
|
| 2 | [is] [adv] [adj] [to-vb] | 10196 |
|
| 3 | [be] [adv] difficult [to-vb] | 2091 |
|
| 4 | [is] [adv] difficult [verb] | 1228 |
|
| 5 | [is] [adv] difficult [to-vb] | 1218 |
|
