| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have [been] [v-ing] for twenty | 12 |
|
| 2 | [verb] [been] [v-ing] for twenty | 12 |
|
| 3 | [verb] been [v-ing] for twenty | 12 |
|
| 4 | [vb -s] [been] [v-ing] for twenty | 5 |
|
