| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficulty in [verb] [pron] [prep] [art] | 10 |
|
| 2 | difficulty in [verb] [pron] [prep] [art] | 10 |
|
| 3 | difficulty in [v-ing] [pron] [prep] [art] | 10 |
|
| 4 | difficulty in [verb] [pron] [prep] the | 7 |
|
| 5 | difficulty in [verb] [pron] [prep] the | 7 |
|
| 6 | difficulty in [verb] [pers pn] [prep] [art] | 6 |
|
