| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [pron] used to [be] | 1772 |
|
| 2 | [Wh det] used to [be] | 208 |
|
| 3 | which [modal v] to [be] | 130 |
|
| 4 | which used [prep] [be] | 69 |
|
| 5 | which used to [be] | 69 |
|
