| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could n't [verb] | 12359 |
|
| 2 | could n't [vb infin] | 12348 |
|
| 3 | [modal v] n't tell | 950 |
|
| 4 | could [adv] tell | 434 |
|
| 5 | could [not/n't] tell | 354 |
|
| 6 | could not tell | 353 |
|
| 7 | could n't tell | 240 |
|
