| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | when [verb] at a | 19 |
|
| 2 | when [v-ing] at a | 11 |
|
| 3 | when [vb pp] at a | 8 |
|
| 4 | when looking at a | 5 |
|
| 5 | when look at a | 5 |
|
