| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] for a [adj] period of | 21 |
|
| 2 | [adv] for a [adj] period of | 20 |
|
| 3 | apart for a [adj] period of | 5 |
|
| 4 | [adv] for a continuous period of | 5 |
|
| 5 | [adv] for a continuous period of | 5 |
|
| 6 | apart for a [adj] period of | 5 |
|
