| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [been] [v-ing] a | 862 |
|
| 2 | [to-vb] [been] a | 404 |
|
| 3 | [to-vb] [v-ing] a | 251 |
|
| 4 | [to-vb] [been] [v-ing] | 194 |
|
