Modal operators of possibility set rules about what’s possible. 

A limiting pattern would be when we use them in the negative. 

"I can’t" or "I just couldn’t"

You might challenge these ‘rules’ by asking questions like:

"What would happen if you did?" or "what’s stopping you" or "just suppose you could…"

Model operators of necessity set rules about what’s necessary. 

A limiting pattern might be when they become burdensome, when someone is telling themselves they ‘have’ to do something even if they don’t want to or it’s not in their best interest.

"I must do" "I have to" "I should"

You might challenge these ‘rules’ by asking questions like:

"What would happen if you didn’t?" "Just suppose you didn’t have to, what would that be like?"

This allows people to identify a different set of possibilities outwith the confines of the ‘rule’.

NLP Practitioners and therapists use the Meta Model both to spot language patterns, and to ask questions that help to move someone beyond the words, back to the experience that created them.  That might be about gathering more information, clarifying meaning, challenging generalisations to identify limitations, and generating choices.