| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | it is [adv] difficult [verb] | 558 |
|
| 2 | it is [adv] [verb] [subord] | 71 |
|
| 3 | it is difficult [verb] [subord] | 59 |
|
| 4 | is [adv] difficult [verb] [subord] | 48 |
|
| 5 | it is [adv] difficult [subord] | 8 |
|
