Re-, -ad-, ek-.
The prefixes "re-" and "ek-" and the suffix "-ad-" are attached to
verbs.
"Re-" has nearly the same meaning as in English, "back" or "again", as
"re-pagi", to pay back; "re-porti", to carry back; "re-jxeti", to throw
back; "re-salti", to rebound; "re-kanti" to sing again; "re-legi", to
read over again.
"-ad-" denotes the continuance or continued repetition of an action;
it means "goes on doing", or "keeps on doing", or "is in the habit
of", or in the past "used to", as "spiri", to breathe, "spirado",
respiration; "movi", to move, "movado", continued movement; "fumi", to
smoke, "fumado", the habit of smoking; "auxdi", to hear, "auxdado", the
sense of hearing.
"Ek-" has the opposite meaning to "-ad-"; it signifies the beginning of
an action, or a short or sudden action, as "kanti", to sing, "ekkanti",
to begin to sing; "ridi", to laugh, "ekridi", to burst out laughing;
"krii", to cry or call, "ekkrii", to cry out; "iri", to go, "ekiri", to
set out; "dormi", to sleep, "ekdormi", to fall asleep.