| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [conj] [pron] is difficult [verb] | 380 |
|
| 2 | [conj] [pron] is often [verb] | 86 |
|
| 3 | [pron] is often difficult [verb] | 59 |
|
| 4 | [conj] [pron] is often difficult | 25 |
|
