| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | but they are [adv] difficult [verb] | 7 |
|
| 2 | but [pers pn] are [adv] difficult [to-vb] | 7 |
|
| 3 | but [pers pn] are [adv] difficult [verb] | 6 |
|
