Esperanto
First, Zamenhof thought about bringing Latin back into use. Although he learned it in school, he realized it was too difficult for normal use. He also studied English and understood that languages did not need to conjugate verbs by person or number. Once he saw two Russian words: швейцарская (reception, derived from швейцар - receptionist) and кондитерская (confectionery, derived from кондитер - confectioner). These words with the same ending gave him an idea. He decided that regular prefixes and suffixes could decrease the number of word roots, which one would need for a communication. Zamenhof wanted the root words to be neutral, so he decided to use word roots from Romance and Germanic languages. Those languages were taught in many schools in many places around the world at that time.