| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [v-ing] [prep] [verb] at | 115 |
|
| 2 | [v-ing] [prep] [vb infin] at | 83 |
|
| 3 | [v-ing] [prep] happen [prep] | 34 |
|
| 4 | [verb] [prep] happen at | 5 |
|
| 5 | [v-ing] [prep] happen at | 5 |
|
