| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [to-vb] [prep] [art] | 64395 |
|
| 2 | difficult [to-vb] [prep] | 1432 |
|
| 3 | difficult [to-vb] [art] | 1328 |
|
| 4 | difficult [prep] [art] | 584 |
|
