| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficult to be [adj] | 88 |
|
| 2 | difficult to be [adj] | 88 |
|
| 3 | [adj] to be sure | 88 |
|
| 4 | difficult to [be] sure | 30 |
|
| 5 | difficult to be sure | 30 |
|
| 6 | difficult to [be] sure | 30 |
|
| 7 | difficult [prep] be sure | 30 |
|
| 8 | difficult to be sure | 30 |
|
| 9 | difficult to be sure | 30 |
|
| 10 | difficult [prep] be sure | 30 |
|
