| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | they must be [prep] [art] | 26 |
|
| 2 | they must be [prep] the | 16 |
|
| 3 | they must be [prep] a | 9 |
|
| 4 | they must be in [art] | 9 |
|
| 5 | they must be of [art] | 6 |
|
