Note
Remember: ss in 1 syllable = ß >ißtss in 2 syllables = ss > es-se
Breakdown of du ißt
du
you
du is informal, so don't use it with strangers, except if they are children. You might use it if your friend brings his buddies along, but generally we tend to first offer someone the right to use du with us.
essen
to eat
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