| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun] is a key part | 7 |
|
| 2 | is a key part [prep] | 10 |
|
| 3 | is a key part [prep] | 10 |
|
| 4 | is a key part of | 9 |
|
| 5 | is a key part of | 9 |
|
