| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficult [to-vb] that | 278 |
|
| 2 | difficult to believe that | 85 |
|
| 3 | difficult to argue that | 28 |
|
| 4 | difficult to imagine that | 24 |
|
| 5 | difficult to see that | 17 |
|
| 6 | difficult to ensure that | 13 |
|
| 7 | difficult to show that | 11 |
|
| 8 | difficult to accept that | 11 |
|
| 9 | difficult to prove that | 10 |
|
| 10 | difficult to say that | 9 |
|
