| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [that] it is difficult [prep] | 21 |
|
| 2 | that it is difficult [prep] | 21 |
|
| 3 | [that] it is difficult for | 16 |
|
| 4 | [that] it is difficult for | 16 |
|
