| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [been] [v-ing] [prep] a [noun] | 405 |
|
| 2 | [v-ing] on [prep] a [noun] | 127 |
|
| 3 | [been] [v-ing] on [prep] [noun] | 62 |
|
| 4 | [been] [v-ing] on [prep] a | 15 |
|
