| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] when [art] [noun sg] | 164 |
|
| 2 | [prep] 1990 [art] [noun sg] | 92 |
|
| 3 | 1990 when [art] [noun sg] | 16 |
|
| 4 | [prep] 1990 when [art] | 13 |
|
