| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | why did [not/n't] he [verb] [prep] | 10 |
|
| 2 | why did [not/n't] he [vb infin] [prep] | 10 |
|
| 3 | why did n't he [verb] [prep] | 10 |
|
| 4 | why did [not/n't] he [verb] to | 5 |
|
