| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [v-ing] [prep] | 81 |
|
| 2 | must have been [v-ing] [prep] | 80 |
|
| 3 | must have been [v-ing] for | 18 |
|
| 4 | must have been [v-ing] in | 14 |
|
| 5 | must have been [v-ing] on | 10 |
|
| 6 | must have been [v-ing] to | 10 |
|
| 7 | must have been thinking [prep] | 7 |
|
| 8 | must have been waiting [prep] | 6 |
|
| 9 | must have been looking [prep] | 6 |
|
| 10 | must have been going [prep] | 5 |
|
| 11 | must have been [v-ing] at | 5 |
|
| 12 | must have been [v-ing] of | 5 |
|
| 13 | must have been [v-ing] about | 5 |
|
