| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be difficult for [noun] [to-vb] | 56 |
|
| 2 | be for [det] [noun] [to-vb] | 39 |
|
| 3 | difficult for [det] [noun] [to-vb] | 28 |
|
| 4 | be difficult for [det] [noun] | 16 |
|
