How easy is Esperanto to learn?
For a native English speaker, we may estimate that Esperanto is about five times as easy to learn as Spanish or French, ten times as easy to learn as Russian, twenty times as easy to learn as Arabic or spoken Chinese, and infinitely easier to learn than Japanese. Many people find that they speak Esperanto better after a few months' study than a language they learned at school for several years.
A knowledge of Esperanto makes it much easier to learn other foreign languages, and there is some evidence that it is actually more efficient to learn Esperanto first, before learning other languages, rather than to study foreign languages directly. For example, one may become more fluent in French by first studying Esperanto for 6 months and then studying French for a year and a half, rather than studying French for two continuous years. The reason may be that Esperanto's regular grammar and word formation and flexible syntax makes it easier to understand other languages' grammar and rules.