| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [adj] to be sure | 51 |
|
| 2 | [be] [adj] to be sure | 49 |
|
| 3 | [is] [adj] to be sure | 37 |
|
| 4 | is [adj] to be sure | 30 |
|
| 5 | [be] difficult to be sure | 18 |
|
| 6 | [be] difficult to be sure | 18 |
|
| 7 | [was/were] [adj] to be sure | 12 |
|
| 8 | was [adj] to be sure | 11 |
|
| 9 | [be] impossible to be sure | 9 |
|
| 10 | [be] impossible to be sure | 9 |
|
| 11 | [be] hard to be sure | 9 |
|
| 12 | [be] hard to be sure | 9 |
|
| 13 | 's [adj] to be sure | 7 |
|
