| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be [prep] [num] [noun pl] ' duration | 52 |
|
| 2 | be of [num] [noun pl] ' duration | 50 |
|
| 3 | be [prep] [num] years ' duration | 49 |
|
| 4 | is [prep] [num] [noun pl] ' duration | 45 |
|
| 5 | be [prep] three [noun pl] ' duration | 26 |
|
| 6 | be [prep] four [noun pl] ' duration | 18 |
|
| 7 | be [prep] two [noun pl] ' duration | 7 |
|
