| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | difficult to be sure | 30 |
|
| 2 | hard to be sure | 12 |
|
| 3 | impossible to be sure | 9 |
|
| 4 | possible to be sure | 8 |
|
| 5 | early to be sure | 6 |
|
| 6 | important to be sure | 6 |
|
