| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] introduced at the [adj] | 8 |
|
| 2 | be introduced at the [adj] | 8 |
|
| 3 | introduced at the [adj] [noun] | 16 |
|
| 4 | introduced at the [adj] [noun sg] | 14 |
|
| 5 | introduced at the [adj] time | 8 |
|
| 6 | introduced at the [adj] time | 8 |
|
