| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [verb] to the | 2650 |
|
| 2 | difficulty [prep] [verb] the | 402 |
|
| 3 | difficulty [prep] [verb] to | 59 |
|
| 4 | difficulty [verb] to the | 12 |
|
