| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | at [art] time when | 1607 |
|
| 2 | at [art] time when | 1607 |
|
| 3 | [prep] a time when | 1443 |
|
| 4 | [prep] a time when | 1443 |
|
| 5 | at a time [adv] | 1379 |
|
| 6 | at a [noun] when | 1379 |
|
| 7 | at a time when | 1342 |
|
| 8 | at a time when | 1342 |
|
