Abstract: A system for preparing a beverage comprises a beverage maker (15) and a cartridge (10) that is removably arranged in the beverage maker (15). The cartridge (10) comprises a beverage making unit (1) having a duct system (30) for conveying flows of steam and flows of liquid. The duct system (30) comprises two combinations of ducts (31, 32; 41, 42), wherein the arrangement of the ducts (31, 32; 41, 42) of each combination is adapted to enabling a flow of steam to perform a pumping action on a flow of liquid. The beverage maker (15) comprises a steam generator (16) having two steam sockets (17, 18), wherein each of the steam sockets (17, 18) is in communication with another combination of ducts (31, 32; 41, 42) of the duct system (30). As each of the combinations of ducts (31, 32; 41, 42) is associated with a different steam inlet (36, 46), and the steam inlets (36, 46) may be located at different positions on the cartridge (10), it is achieved that the duct system (30) may be of a relatively simple design.