| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | at an [noun sg] | 1270 |
|
| 2 | at an angle | 214 |
|
| 3 | at an end | 129 |
|
| 4 | at an average | 67 |
|
| 5 | at an auction | 47 |
|
| 6 | at an altitude | 39 |
|
| 7 | at an exhibition | 36 |
|
| 8 | at an age | 31 |
|
| 9 | at an emergency | 29 |
|
| 10 | at an undervalue | 25 |
|
| 11 | at an advantage | 24 |
|
| 12 | at an event | 20 |
|
| 13 | at an army | 15 |
|
| 14 | at an address | 14 |
|
| 15 | at an inquest | 14 |
|
| 16 | at an election | 12 |
|
| 17 | at an inn | 11 |
|
| 18 | at an area | 11 |
|
| 19 | at an interest | 10 |
|
| 20 | at an exchange | 9 |
|
| 21 | at an elevation | 8 |
|
| 22 | at an interpretation | 8 |
|
| 23 | at an audience | 8 |
|
| 24 | at an animal | 8 |
|
| 25 | at an engineering | 8 |
|
| 26 | at an airport | 7 |
|
| 27 | at an interval | 6 |
|
| 28 | at an impasse | 6 |
|
| 29 | at an adult | 6 |
|
| 30 | at an inquiry | 6 |
|
