| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | been [verb] in [num] | 569 |
|
| 2 | been [vb pp] in [num] | 561 |
|
| 3 | be introduced in [num] | 176 |
|
| 4 | [be] introduced in [num] | 176 |
|
| 5 | been introduced in [adj] | 20 |
|
| 6 | been introduced [prep] [num] | 14 |
|
| 7 | been introduced [prep] [num] | 14 |
|
| 8 | been introduced in [num] | 9 |
|
| 9 | been introduce in [num] | 9 |
|
| 10 | [been] introduced in [num] | 9 |
|
