Players in During Spring, Summer and Winter need to determine which card has been removed from the deck, and to do that they'll need to ask others which cards they hold in hand — but not directly.
The deck consists of four cards for each season numbered 1, 1, 2 and 3, along with a "rainy season" card when playing with four players. At the start of a round, shuffle the cards, place one in the center of the table, then distribute the rest of the cards to the players. On a turn, a player asks one of two types of questions of another player: "How many cards do you hold of a certain number?" or "What's the sum of the spring (summer, etc.) cards that you hold?" In the latter case, as a cost you must place one card from your hand on display, revealing information to all players.
When you think you know which card is in the middle of the table, take a peek; if you're correct, you score points and the game ends as soon as someone has collected six points.