| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] has [been] a key [noun] | 14 |
|
| 2 | [noun sg] has [been] a key [noun] | 10 |
|
| 3 | has [been] a key [noun] [prep] | 17 |
|
| 4 | has [been] a key [noun] [prep] | 17 |
|
| 5 | has [been] a key [noun] in | 11 |
|
| 6 | has [been] a key [noun] in | 11 |
|
| 7 | has [been] a key [noun] of | 5 |
|
| 8 | has [been] a key [noun] of | 5 |
|
