| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | why do n't [pers pn] [vb infin] back | 27 |
|
| 2 | why do n't [pron] [vb infin] back | 27 |
|
| 3 | why do n't you [vb infin] back | 22 |
|
| 4 | why do n't you [vb infin] back | 22 |
|
| 5 | why do n't [pron] [vb infin] back | 20 |
|
| 6 | why do n't [pron] go back | 16 |
|
| 7 | why do n't [pron] come back | 9 |
|
| 8 | why did n't [pron] [vb infin] back | 6 |
|
