| be unclear | 749.91 | Quite why he left is unclear. | ||
| remain unclear | 136.14 | A motive for the fires remained unclear. | ||
| seem unclear | 1.51 | A motive seems unclear. | ||
| become unclear | 0.99 | But the writer part became increasingly unclear. | ||
| appear unclear | 0.33 | But even the fate of the military accord appeared unclear. |