| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have not changed | 216 |
|
| 2 | have n't changed | 210 |
|
| 3 | has [not/n't] changed | 168 |
|
| 4 | have [not/n't] changed | 134 |
|
| 5 | had [not/n't] changed | 120 |
|
