| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | be required [prep] [adj] | 30 |
|
| 2 | be required [prep] [be] | 26 |
|
| 3 | required [prep] [be] [adj] | 22 |
|
| 4 | be [prep] [be] [adj] | 16 |
|
