| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] long period [prep] | 159 |
|
| 2 | [verb] [prep] period [prep] | 128 |
|
| 3 | [verb] [prep] long period | 111 |
|
| 4 | [verb] long period [prep] | 47 |
|
