| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | can [be] maintained [conj] | 14 |
|
| 2 | can only [be] [conj] | 14 |
|
| 3 | can only [be] maintained | 12 |
|
| 4 | only [be] maintained [conj] | 6 |
|
