There are only 2 cards on the ground. (sometimes more than 2) If you collect them those 2 cards by matching one with your Hand card and the other with your flipped card, meaning you've just Cleared the ground, you also receive one bonus Plain card each from the other players' Collection square.
There are only 2 cards on the ground. (sometimes more than 2) If you collect them those 2 cards by matching one with your Hand card and the other with your flipped card, meaning you've just Cleared the ground, you also receive one bonus Plain card each from the other players' Collection square.
A set of action on your turn

Let's Play
Now, 3 players start the round. Each holds 7 Hand cards, showing only to oneself and all 6 Ground cards are faced up after one player dies.
On your turn, you put down one Hand card to match a pair with a Ground card of the same month, and then flip one card from the Flip pile to possibly match another Ground card.(if you flip a Wild card, you flip one more card) When there is a match(es) of pairs, you collect them into your Collection square. Even if there is no Ground card for you to match with your Hand card, you still need to complete this set of action on each turn.
A set of action
i) One Hand card onto ground
-> ii) One Flip card onto ground
-> iii) Collect any matched cards
-> iv) Display into your Collection square