[tenderfoot]

The words themselves don't matter - it is more about your attitiude and energy. You can say 'pizza' for your word they don't care.
Just put them back in place if they break. Try to create the action without touching them. They have learned that mom touches us to make us do something - but they didn't really choose it on their own. Teach the stay too. So when you say 'sit' then your follow up with 'stay' so that they learn patience.
When you release them use happy energy in your tone and body language so they can feel the difference. Be firmer in your tone when you say stay. They need to hear the difference.