| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] [prep] a short period [prep] | 14 |
|
| 2 | [adv] [prep] a short period [prep] | 12 |
|
| 3 | [adv] for a short period [prep] | 8 |
|
| 4 | [adv] [prep] a short period of | 8 |
|
