| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [coord] [pron] [be] difficult [verb] | 263 |
|
| 2 | [pron] [be] often difficult [verb] | 78 |
|
| 3 | [coord] [pron] [be] often [verb] | 74 |
|
| 4 | [coord] [pron] [be] often difficult | 14 |
|
