have you seen them
When did you see them?
Le avete viste andare a bordo?
Did you see them go on board?
Have you seen them recently?
Le avete viste la scorsa notte?
Did you see them last night?
Have you seen them or not?
Le avete viste questa mattina?
Did you see them this morning?
Have you seen them around?
Didn't you see them at dinner?