| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] difficult [to-vb] [conj] [art] | 66 |
|
| 2 | [adv] difficult [to-vb] [adv] [art] | 35 |
|
| 3 | [adv] [to-vb] [adv] [conj] [art] | 34 |
|
| 4 | [adv] difficult [to-vb] [adv] [conj] | 31 |
|
| 5 | difficult [to-vb] [adv] [conj] [art] | 9 |
|
