When we tell of someone doing a certain action we often want to allude
to some circumstance concerning that action, such as the time, or place,
or manner in which it was done, that is, when, or where, or how it was
done.
In the sentences--Yesterday I met your son, "Hieraux mi renkontis vian
filon"; He will go in the evening, "Li iros vespere"; They sat there,
"Ili sidis tie"; She will remain at home, "Sxi restos hejme"; Good
children learn diligently, "Bonaj infanoj lernas diligente"; I will do
it with pleasure, "Mi faros gxin plezure", the words "hieraux, vespere",
show the time, "tie, hejme", show the place, and "diligente, plezure",
show the manner of the action.
(Because these words relate to the verb they are called ADVERBS).
Adverbs may be formed from any word whose sense admits of it, and
especially from adjectives, by means of the termination "e", as "bona",
good, "bone", well; "antaux" before, "antauxe", previously or formerly;
"mateno", morning, "matene", in the morning; "sekvi", to follow,
"sekve", consequently.
When we want the adverb to show "direction towards" any place, time,
etc., either actually or figuratively, "n" is added, as "Li alkuris
hejmen", He ran home. "Ili levis unu manon supren", They raised one
hand upwards. "Antauxen"! Forward! ("n" is also added to nouns to show
direction towards. "Li eniris en la domon", He entered into the house).
Some adverbs are used with adjectives and other adverbs to show the
"degree" of the quality, quantity, etc., as The paper is "very" white,
La papero estas "tre" blanka. "Too" much speaking tires him, La "tro"
multa parolado lacigas lin. I am "as" strong "as" you, Mi estas "tiel"
forta, "kiel" vi (estas forta). He came "very" early, Li venis "tre"
frue.
The following words are in themselves adverbs, and need no special
ending:--