| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] have been [v-ing] [prep] several | 8 |
|
| 2 | [noun] have [been] [v-ing] [prep] several | 8 |
|
| 3 | [noun] have [been] [v-ing] for several | 7 |
|
| 4 | [noun] had [been] [v-ing] [prep] several | 5 |
|
