| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [is] difficult believe that [adj] | 8 |
|
| 2 | [is] difficult to believe that [adj] | 8 |
|
| 3 | is difficult believe that [adj] | 8 |
|
| 4 | [is] difficult believe that [det] | 6 |
|
