| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficult [to-vb] the [noun] [prep] | 314 |
|
| 2 | [to-vb] [coord] the [noun] [prep] | 135 |
|
| 3 | difficult [to-vb] [coord] the [noun] | 15 |
|
