| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | at a [noun sg] when [noun] | 356 |
|
| 2 | a [noun sg] when [adj] [noun] | 181 |
|
| 3 | at a [noun sg] when [adj] | 138 |
|
| 4 | at a [noun sg] [adj] [noun] | 22 |
|
