| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | have [been] [v-ing] [prep] [adj] | 1054 |
|
| 2 | could have [been] [v-ing] [prep] | 31 |
|
| 3 | could have [been] [prep] [adj] | 30 |
|
| 4 | could have [been] [v-ing] [adj] | 5 |
|
