| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [noun sg] [verb] been operating [prep] | 13 |
|
| 2 | [noun sg] have been operating [prep] | 13 |
|
| 3 | [noun sg] [vb -s] been operating [prep] | 10 |
|
| 4 | [noun sg] has been operating [prep] | 10 |
|
| 5 | [noun sg] [verb] been operating for | 6 |
|
| 6 | [noun sg] [verb] been operating for | 6 |
|
