| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [subord] it is [verb] | 3898 |
|
| 2 | difficult it is [verb] | 69 |
|
| 3 | difficult [subord] it [verb] | 30 |
|
| 4 | difficult [subord] it is | 20 |
|
