| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have [adv] been a feature | 18 |
|
| 2 | [vb -s] [adv] been a feature | 16 |
|
| 3 | has [adv] been a feature | 16 |
|
| 4 | [verb] always been a feature | 9 |
|
| 5 | [verb] also been a feature | 5 |
|
