| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [vb -s] [be] [v-ing] [prep] years | 18 |
|
| 2 | [vb -s] [be] [v-ing] [prep] three | 15 |
|
| 3 | [be] [v-ing] [prep] three years | 15 |
|
