| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [is] difficult [prep] [pron] [verb] | 58 |
|
| 2 | difficult [prep] [pron] [verb] [prep] | 41 |
|
| 3 | [is] [prep] [pron] [verb] [prep] | 31 |
|
| 4 | [is] difficult [prep] [pron] [prep] | 7 |
|
