I thought it would be labrum. What case is "labro"?
Thanks - so I take it that the preposition "in" demands an ablative case.
When you are talking about a location with no movement, you use the ablative. "I am in the city." -> in urbe sum.
If there is motion 'into' then in takes the accusative. "I go into the city." -> in urbem eo.
No, not necessarily: "in" takes the ablative for senses like 'in, on, at'; but it could also take the accusative for senses like 'into, toward, against', depending.
I thought it was 'ego balneo lavo' ??
'ego lavo' is just 'I wash'. And strictly speaking the 'ego' is redundant; you'd often write just 'lavo' for 'I wash'.
To say 'I wash myself' you need the accusative pronoun 'me' as well ('me lavo').
Duolingo says that my answer "lavo me in labro " is incorrect!