| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [pron] [to-vb] [adj] [noun] | 633 |
|
| 2 | difficult [prep] [pron] [to-vb] [adj] | 36 |
|
| 3 | difficult [prep] [pron] [to-vb] [noun] | 20 |
|
