| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] difficult [to-vb] [coord] [adv] | 11 |
|
| 2 | more difficult [to-vb] [conj] [adv] | 11 |
|
| 3 | [adv] difficult [to-vb] [subord] [adv] | 10 |
|
| 4 | [adv] difficult [to-vb] and [adv] | 8 |
|
| 5 | [adv] difficult [to-vb] and [adv] | 8 |
|
| 6 | [adv] difficult [to-vb] than [adv] | 7 |
|
| 7 | [adv] difficult [to-vb] than [adv] | 7 |
|
