| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | not [verb] certain | 27 |
|
| 2 | [not/n't] [vb infin] certain | 26 |
|
| 3 | n't [verb] certain | 8 |
|
| 4 | [not/n't] have certain | 7 |
|
| 5 | [not/n't] [to-vb] certain | 5 |
|
| 6 | [not/n't] have certain | 5 |
|
