| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb mod] [be] [v-ing] a | 819 |
|
| 2 | [vb mod] [be] [v-ing] at | 519 |
|
| 3 | [vb mod] [be] at a | 80 |
|
| 4 | [be] [v-ing] at a | 53 |
|
