| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [adv] difficult [verb] but | 9 |
|
| 2 | be [adv] difficult [verb] but | 9 |
|
| 3 | [is] [adv] difficult [verb] but | 7 |
|
| 4 | is [adv] difficult [verb] but | 7 |
|
