| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | at [adv] two years ' [noun] | 8 |
|
| 2 | at [adv] two years ' [noun] | 8 |
|
| 3 | at [adv] two years ' [noun] | 8 |
|
| 4 | at [adv] two years ' [noun sg] | 8 |
|
| 5 | at least two years ' [noun] | 7 |
|
| 6 | at least two years ' [noun] | 7 |
|
