I didn't find any satisfactory reference about the usage of the pronoun "beide". It means "both" and probably comes from the same source too, but I'm confused about the article to use in front of it. Suppose you want to say:
The girls go to the cinema, they both like movies.
Would you then write:
Die Mädchen gehen ins Kino, sie beide mögen Filme ?
Is this correct? In this case you have the personal pronoun preceding "beide". One other case would be the one where you have no personal pronoun. So, I have three attempts to check:
Die beiden Männer lachen,
Beide der Männer lachen,
Beide Männer lachen.
Which one is right? And, as a consequence, what is the proper usage of "beide", does it require the article?