| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | is [adv] [verb] | 48380 |
|
| 2 | [adv] difficult [verb] | 3637 |
|
| 3 | is difficult [verb] | 1946 |
|
| 4 | is [adv] difficult | 1587 |
|
