observed, watched
I've been watching them all day.
— Harry Potter y la piedra filosofal (2001)
Quién en Moscú no ha estado, la belleza no ha observado.
Whoever has not been to Moscow, has not seen its beauty.
— Брат (1997)
You are being watched.
I am being watched.
Él estaba consciente de estar siendo observado.
He was aware that he was being watched.
Por un largo tiempo te he observado.
For a long time I have watched you.