| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] have been [v-ing] [prep] | 1813 |
|
| 2 | [noun] may have been [prep] | 66 |
|
| 3 | [noun] may have been [v-ing] | 47 |
|
| 4 | may have been [v-ing] [prep] | 40 |
|
