| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | has been [verb] for [adv] | 98 |
|
| 2 | has been [v-ing] for [adv] | 31 |
|
| 3 | have been operating for [adv] | 6 |
|
| 4 | [verb] been operating for [adv] | 6 |
|
| 5 | [vb -s] been operating for [adv] | 5 |
|
| 6 | has [been] operating for [adv] | 5 |
|
| 7 | has been operate for [adv] | 5 |
|
| 8 | has be operating for [adv] | 5 |
|
| 9 | has [be] operating for [adv] | 5 |
|
| 10 | has been operating [prep] [adv] | 5 |
|
| 11 | has been operating [prep] [adv] | 5 |
|
| 12 | has been operating for [adv] | 5 |
|
