| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [vb infin] [prep] | 2036 |
|
| 2 | then [vb infin] [prep] | 497 |
|
| 3 | [prep] then [prep] | 135 |
|
| 4 | [prep] then [vb infin] | 48 |
|
