Many words in English are based on the same roots words, and knowing what these mean can help us with spellings.
The prefixes 'audi-' and 'aqua-' come from Latin words meaning 'hearing' and 'water'. They form part of a large number of words in English.
An aquarium is a tank or building in which fish and other water creatures are kept.
An auditorium is the part of a theatre where people sit to watch and listen.