| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | a long period [prep] time | 102 |
|
| 2 | a long period [prep] time | 102 |
|
| 3 | a long period of time | 102 |
|
| 4 | a long period [prep] time | 102 |
|
| 5 | a long period [prep] time | 102 |
|
| 6 | a long period of time | 102 |
|
