| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficulty in [verb] the [adj] | 85 |
|
| 2 | in [verb] to the [adj] | 72 |
|
| 3 | difficulty in [verb] to the | 11 |
|
| 4 | difficulty in [verb] to [adj] | 6 |
|
