| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] in [v-ing] [pron] [prep] | 195 |
|
| 2 | difficulty [prep] [v-ing] [pron] [prep] | 35 |
|
| 3 | difficulty in [v-ing] [pron] [prep] | 27 |
|
| 4 | difficulty in [verb] [pron] [prep] | 27 |
|
