| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | an [adj] period [prep] [noun sg] | 58 |
|
| 2 | an indefinite [noun] [prep] [noun sg] | 11 |
|
| 3 | an indefinite [noun sg] [prep] [noun sg] | 11 |
|
| 4 | an indefinite period [prep] [noun sg] | 6 |
|
| 5 | an indefinite period [prep] [noun] | 6 |
|
| 6 | an indefinite period [prep] [noun sg] | 6 |
|
| 7 | [art] indefinite period [prep] [noun sg] | 6 |
|
| 8 | a indefinite period [prep] [noun sg] | 6 |
|
| 9 | [art] indefinite period [prep] [noun sg] | 6 |
|
