120. Adverbs may be derived from prepositions whose sense permits, by
use of the adverb ending "-e":
Antauxe li studis la geometrion, previously he studied geometry.
Poste li studis la germanan, afterwards he studied German.
Li marsxis antauxe, ne malantauxe, he walked in front, not behind.
Dume la viroj staris cxirkauxe, meanwhile the men stood roundabout.
Ili venis kune kaj sidis apude, they came together and sat near by.