| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb -s] [been] [v-ing] | 4747 |
|
| 2 | [vb -s] [been] a | 3898 |
|
| 3 | [been] [v-ing] a | 862 |
|
| 4 | [vb -s] [v-ing] a | 328 |
|
