| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] [prep] a [adj] period of | 223 |
|
| 2 | [noun] [prep] a long [noun] of | 198 |
|
| 3 | [noun] [prep] a long period [prep] | 81 |
|
| 4 | [noun] [prep] a long period [prep] | 81 |
|
| 5 | [noun] [prep] [art] long period of | 78 |
|
| 6 | [noun] [prep] [art] long period of | 78 |
|
| 7 | [noun] [prep] a long period of | 70 |
|
| 8 | [noun] [prep] a long period of | 70 |
|
