Jass play is very hierarchical. When two teams play, they play a tourney, which may consist of any number of matches (usually odd, so a winner is determined). A Jass match consists of the number of games required for a team to reach 2500 points. Each game has 9 hands (one for each card dealt). Each hand has 4 cards, one thrown by each player.
Before playing a hand, one of the teams must choose a trump for that game. For the first match of a tourney, the player with the 10 of Hearts chooses a trump. After selecting (and announcing) a trump, that player plays a card to start the hand. Play proceeds to the right, with each player, in turn, playing a card until 4 cards are thrown. That completes the hand and the team that won that hand collects those cards. The player that threw the card that won that hand throws the first card in the next hand. Play continues this way until the game is finished (all cards have been played).
Trump passes to the right, too. That is, the player to the right of the last player to choose trump selects trump for the next game. In this way, the opportunity to select trump is passed from player to player in order and alternates by team.