| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [adv] [adv] [vb infin] back | 19 |
|
| 2 | could [adv] [adv] [vb infin] back | 13 |
|
| 3 | could no [adv] [vb infin] back | 8 |
|
| 4 | could no [adv] [vb infin] back | 8 |
|
| 5 | could [adv] longer [vb infin] back | 8 |
|
| 6 | could [not/n't] [adv] [vb infin] back | 6 |
|
| 7 | could not [adv] [vb infin] back | 6 |
|
