Words

How many words does/did your 15 month old say? I know some babies are different but just kind of seeing others responses. Cam mostly babbles, can say dad/daddy when he wants to, use to say mama and then he stopped. He understands almost everything I say to him. We speak to him in Tagalog but I'd say 70% is English. I'd like for him to know Tagalog since it's a lost language here in USA but what are ways to get him to say new words? I do read to him every night and we started on little flash cards I found at Target.