| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | reason why i | 189 |
|
| 2 | reason [Wh adv] i | 189 |
|
| 3 | reason [Wh adv] i | 149 |
|
| 4 | reasons [Wh adv] i | 40 |
|
