| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | a [adj] period during | 21 |
|
| 2 | a long period during | 8 |
|
| 3 | a brief period during | 7 |
|
| 4 | a brief period during | 7 |
|
| 5 | a long period during | 6 |
|
