| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [adv] than three years [unc] [noun] | 9 |
|
| 2 | [adv] than three years [unc] [noun] | 9 |
|
| 3 | less than three years [unc] [noun] | 5 |
|
| 4 | less than three years [unc] [noun] | 5 |
|
