de.toml

'email address.gender' = 'feminine'

# https://forum.djangoproject.com/t/grammatical-error-in-german-translation-of-form-validation/34478
['%(model_name)s with this %(field_labels)s already exists.'.'gender:field_labels']
feminine = '%(model_name)s mit dieser %(field_labels)s existiert bereits.'
other = '%(model_name)s mit diesem %(field_labels)s existiert bereits.'
# to properly handle multiple fields in above example we'd need to move "this" into field_labels
'%(model_name)s with %(field_labels)s already exists.' = '%(model_name)s mit %(field_labels)s existiert bereits.'  # this dative can be assumed, not verbose
['this %(field_label)s'.'gender:field_label']
feminine = 'dieser %(field_label)s'
other = 'diesem %(field_label)s'
# this way we should be able to produce 'mit dieser E-Mail-Adresse und diesem Login'