In this series, we are talking through the NMJL newsletter question and answer section.
Question number two says, Please explain number seven on the back of the card under “calling for a discard.“ What is meant by “number and type of tiles?“ on the NMJL card, it states that a player may change the number and type of tiles in an exposure up until their discard.
Once you call and place a tile on top of your rack, you may add or subtract from the exposure until you either initiate a joke or exchange or discard. The called tile may not be returned to the table.
Once you call a tile and place it on top of your rack, you must make an exposure that utilizes that tile. You cannot throw that tile back into the discard, and once you’ve made your exposure of tiles, you can only change the number of tiles that you’re exposing up until you either start a joke or swap or you and your turn with a discard. Once those things happen, you must have that exposure as is in your hand to win the game. 
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