Sign

признак

priznak

(a fact that shows that something exists or may happen)

подпи́сывать

podpísyvatʹ

(to make (a document) official by writing one's signature)

подпи́сываться

podpísyvatʹsja

(to make (a document) official by writing one's signature)

подписа́ть

podpisátʹ

(to make (a document) official by writing one's signature)

подписа́ться

podpisátʹsja

(to make (a document) official by writing one's signature)