| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficult it is [prep] [noun] | 13 |
|
| 2 | difficult it is [prep] [noun] | 13 |
|
| 3 | difficult it is for [noun] | 11 |
|
| 4 | difficult it is for [noun] | 11 |
|
| 5 | difficult it is [prep] [noun pl] | 8 |
|
