| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [coord] [prep] a [noun] of | 1905 |
|
| 2 | [coord] [prep] a [noun sg] of | 1807 |
|
| 3 | [conj] [prep] a period of | 51 |
|
| 4 | [coord] [prep] [art] period of | 44 |
|
| 5 | [coord] [prep] a period [prep] | 35 |
|
| 6 | [coord] [prep] a period of | 32 |
|
| 7 | [coord] [prep] a period of | 32 |
|
