die Matratze
mattress
A thick, padded surface that is used as part of a bed for sleeping or lying down.
Nach zehn Jahren war es Zeit für eine neue Matratze.
After ten years, it was time for a new mattress.

mattress
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mattress
A thick, padded surface that is used as part of a bed for sleeping or lying down.
Nach zehn Jahren war es Zeit für eine neue Matratze.
After ten years, it was time for a new mattress.

'Matratze' (mattress) is the base word for many specific types of mattresses. If you know this word, you can more easily understand compounds like 'Luftmatratze' (air mattress), 'Federkernmatratze' (spring mattress), or 'Kaltschaummatratze' (cold foam mattress).
Im Sommer nehme ich immer eine Luftmatratze mit an den See.
In summer, I always take an air mattress with me to the lake.
The preposition 'auf' (on) is used with 'Matratze' (mattress). You use the dative for a position and the accusative for a direction.
Das Kind schläft tief und fest auf der neuen Matratze.
The child is sleeping soundly on the new mattress.
Common adjectives are 'eine harte Matratze' (a firm mattress) or 'eine weiche Matratze' (a soft mattress). A typical verb is 'die Matratze wenden' (to turn the mattress), which means to flip it over.
Man sollte seine Matratze alle paar Monate wenden.
You should turn your mattress every few months.
bed
'das Bett' and 'die Matratze' are closely connected, but they do not mean the same thing. The 'Bett' is the whole piece of furniture used for sleeping. The 'Matratze' is the soft surface in the bed that you lie on. Learners may confuse the words because both are directly connected with sleeping. When you are talking about the piece of furniture as a whole, you say 'Bett'; when the lying surface or comfort is the issue, 'Matratze' is more precise.

Antons Matratze ist zu hart, deshalb schläft er schlecht.
Anton's mattress is too hard, so he sleeps badly.
Im Gästezimmer steht ein kleines Bett.
There is a small bed in the guest room.