One thing I really like about #Esperanto is the infix -iĝ- which refers to becoming, it basically makes words intransitive, like:
So ruĝa = red, ruĝiĝi = to blush
naski = to give birth, naskiĝi = to be born
edzi = to marry, edziĝi = to get married
There is a similar (maybe annoyingly so) infix for "to make/cause", -ig-, which makes them transitive:
morti = to die, mortigi = to kill
riĉa = rich, riĉigi = to become rich, riĉigi = to enrich
Those and the question marker "ĉu" are features I often wish I had in other languages.
These are just two of the affixes, by the way. I really liked the whole system of them, it makes it pretty easy to quickly build a big vocabulary, and it's very expressive: https://en.wikibooks.org/wiki/Esperanto/Appendix/Table_of_affixes
-ul = person characterized by (juna = young, junulo = a youth)
-ej = place characterized by (lerni = to learn, lernejo = school)
-ilo = instrument (skribi = write, skribilo = writing implement)
They can also be used by themselves, like:
iĝi = to become
ulo = dude, chap
ilo = tool
