| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | not know the extent to which | 5 |
|
| 2 | not know the extent to which | 5 |
|
| 3 | not know the extent to [pron] | 5 |
|
| 4 | not know the extent to [Wh det] | 5 |
|
