| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | at [adv] [prep] | 3658 |
|
| 2 | at [adv] [prep] | 3518 |
|
| 3 | [prep] once [prep] | 348 |
|
| 4 | at once [prep] | 278 |
|
| 5 | at once [prep] | 278 |
|
