"Do they use the euro in Germany?"

Translation: An úsáideann siad an euro sa Ghearmáin?

[Cait48]

This is one where I feel like using "úsáidtear".

[smrch]

An úsáidtear an Euro sa Ghearmáin would be much better.

[Ainm10]

As said by others, the autonomous form of the present indicative should be used here.

[harrycline]

Why ' i Sasana' but not 'i Ghearmain'

[Cait48]

England = Sasana,
Germany = an Ghearmáin
When 'an' is part of the name of the country, you have 'sa' instead of 'i.'

[Ainm10]

Just to add to what Cáit wrote, if the Irish for Germany didn't include the article, you you still be wrong as i causes eclipsis rather than lenition.