| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] a long [noun] [prep] | 927 |
|
| 2 | [prep] a long [noun sg] [prep] | 890 |
|
| 3 | [prep] a [adj] period [prep] | 871 |
|
| 4 | [prep] [art] long period [prep] | 198 |
|
| 5 | [prep] a long period [prep] | 179 |
|
