Babys first words

My god daughter will be 18 months old the beginning of august, she already says tons of words, but we are trying to teach her some more, what are some words that would be easy for a baby to learn?

The words she already says- mama, woof woof, pup pup,...

kitty, meow,tweet tweet, spongebob bun-ba, bottle baba, baby is also baba but there is a difference, no, mine, eww, stinky, cool, fish, bella, bunny, bye bye, hi, haley-go-bye, drink... She has said my name a couple times emmalie when shes mad and wanted me to pay attention to her, but normally calls me em-mama
Like I said, she says quite a few words, and also knows the noise a bird, cat, dog, horse, pig, duck, and gary from spongebob make.. Also she says mmm when she wants food.. And a whole bunch of other words that no one understands yet..
She has never said dada, because he has been in iraq for most of her life.. So she doesnt know what dada is..

Any ideas?

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Well she will mimic small words. Try counting and abcs everyday so she becomes familar with them. Also get a couple pictures of her father and laminate them and cut them in circles, squares are not safe and can scratch. Give her the laminated pictures to hold on to and teach her the word dada. Because they are laminated they will not get ruined. Nothing would brighten his day more than for her to recognize him when he comes home, bc of the pictures, and says dada.