"The children are cheerful because it is snowing."
Translation:La infanoj estas gajaj ĉar neĝas.
I entered the following and got it right... but wondering if it really is right ... or if duoling just thought I made a typo.
la infanoj gajas cxar negas.
Esperanto is so cool. I wasnt sure if I could use gaj- as a verb... and it worked.
I'm a big fan myself.
As a side note, keep in mind that it is not always the case that turning adjective X into a verb will mean "estas X". For example, rapidi does not mean "esti rapida" (to be fast). It means "to hurry." Turning a nonverbal root into a verb does not always result in a verb with a clear, agreed upon meaning.