Hi, this is Gary Zyer for Expert Village.
Let’s now see how knocking is done. Let’s say you have a hand with some melds and some
deadwood cards. If your deadwood cards are equal to ten points or less, which is a requirement
for knocking, then you can discard one card face down, after completing your draw, and
expose your hand, arranging it into as many sets or runs that are possible. Any remaining
cards from your hand that don’t fit into a valid combination are added up and put to
the side. Remember that if you want to knock, these unmatched cards, your deadwood cards,
cannot equal more than ten points. Now your opponent, who didn’t knock, opens up his hand
and arranges his cards into melds and deadwood. As long as you, the knocker, didn’t present
a Gin hand, your opponent now has an option to lay off any of his unmatched cards by using
them to extend the sets and runs laid down by you. They can add, for example, a forth
card to a group of three or they can add a card of the same suite to a sequence. But,
the person who knocks does not have that option. Only the opponent can use the other person’s
melds to lay off his unmatched cards.