| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has [been] [v-ing] [prep] | 1064 |
|
| 2 | [been] [v-ing] [prep] a | 582 |
|
| 3 | has [been] [v-ing] a | 169 |
|
| 4 | has [been] [prep] a | 130 |
|
