Please choose the correct ending to complete the given sentence: Food and Entertaining: [header] How to use a keurig machine [title] Fill the water reservoir. [step] Lift the lid off the water reservoir, located either on the left side or at the back of your machine. Depending on your model, either pull out the reservoir from the left side of the machine to fill it, or use a cup or mug to pour water into the back reservoir to the desired quantity.

Ending1: [substeps] Place a cup or mug on top of the water reservoir when filling the machine if that's your first time using the machine. [title] Run the keurig machine through a motion sensor. Ending2: [substeps] Don't fill water to above the line on the reservoir that says " max fill. " it's best to use filtered or spring water, as hard water from the tap may leave mineral buildup in the machine over time. Ending3: [title] Add heat and wait for the water to pour out. [step] Make sure there are no vapors or bubbles coming out of the solution when you take the lid off. Ending4: [substeps] The type of keurig you use can vary wildly from machine to machine. So it's best to have a general idea of the machine type you want before moving on to filling the machine.

Answer format: ending1/ending2/ending3/ending4