| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [Wh adv] it is [verb] | 483 |
|
| 2 | [Wh adv] difficult it is | 79 |
|
| 3 | difficult it is [verb] | 69 |
|
| 4 | [Wh adv] difficult it [verb] | 9 |
|
