| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must [verb] lifespan quality assurer | 5 |
|
| 2 | must [verb] lifespan quality assurer | 5 |
|
| 3 | must [verb] lifespan quality [noun] | 5 |
|
| 4 | must [verb] lifespan quality [noun sg] | 5 |
|
