| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] [be] difficult [to-vb] [noun] | 172 |
|
| 2 | [noun sg] [pron] [be] difficult [to-vb] | 133 |
|
| 3 | [noun sg] [pron] [be] [to-vb] [noun] | 76 |
|
