| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | could [not/n't] [vb infin] back | 68 |
|
| 2 | could [not/n't] [vb infin] back | 68 |
|
| 3 | could n't [vb infin] back | 50 |
|
| 4 | could [not/n't] go back | 24 |
|
| 5 | could not [vb infin] back | 18 |
|
| 6 | could [not/n't] get back | 10 |
|
| 7 | could [not/n't] hold back | 6 |
|
