| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | been [v-ing] [prep] twenty year | 8 |
|
| 2 | [be] [v-ing] [prep] twenty year | 8 |
|
| 3 | be [v-ing] [prep] twenty year | 8 |
|
| 4 | [been] [v-ing] [prep] twenty year | 8 |
|
| 5 | [v-ing] [pers pn] [prep] twenty year | 5 |
|
| 6 | [v-ing] [pron] [prep] twenty year | 5 |
|
