| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | do [not/n't] know for certain | 11 |
|
| 2 | [verb] [not/n't] know for certain | 11 |
|
| 3 | [vb base] [not/n't] know for certain | 9 |
|
| 4 | do [not/n't] know for certain | 9 |
|
| 5 | be [not/n't] know for certain | 7 |
|
| 6 | [be] [not/n't] know for certain | 7 |
|
| 7 | is [not/n't] know for certain | 6 |
|
| 8 | [is] [not/n't] know for certain | 6 |
|
| 9 | [not/n't] know for certain [conj] | 6 |
|
