Esperanto nouns have two cases, nominative and accusative. The accusative is used to show the object of a transitive verb (the person or thing affected by the action of the verb).
Kiun mi vidas? – Whom do I see?
Mi vidas amikon – I see a friend.
Do not use the accusative after the verb "to be" or its equivalents.
Adjectives agree with the nouns they qualify: they take the same -j and -n endings.
Vi estas bona amiko – You're a good friend.
Vi estas bonaj amikoj – You're good friends.
Vi havas bonan amikon – You have a good friend.
Vi havas bonajn amikojn – You have good friends.
Esperanto expresses other case relationships through the use of prepositions. The English possesive is rendered by de:
La libroj de mia frato. – My brother's books.
Base form: -i
labori – to work
Present tense: -as
mi laboras – I work
vi laboras – You work
li/ŝi laboras – He/she works
ni laboras – We work
ili laboras – They work
Past tense: -is
mi laboris – I worked.
vi laboris – You worked.
li/ŝi laboris – He/she worked.
ni laboris – We worked.
ili laboris – They worked.
Future tense: -os
mi laboros – I will work.
vi laboros – You will work.
li/ŝi laboros – He/she will work.
ni laboros – We will work.
ili laboros – They will work.
The conjuction ke
is used to introduce a noun clause. Unlike its English equivalent "that"
it cannot be omitted, and
it is usually preceded by a comma.
Vi vidas ke mi manĝas. – You see that I'm eating.
Li diras ke li iros. – He says he'll go.
The prefix mal-
changes the meaning of a word to its opposite.
bona – good
malbona – bad
granda – big, great
malgranda – little, small
bela – beautiful
malbela – ugly
The prefix ge-
denotes both sexes together:
gefratoj – brothers and sisters
gepatroj – parents
bonvolu – please, be so good as to
dankon – thank you
saluton – hello, hi
The usual order of words in the sentence is subject-verb-object, as in English. However, since the accusative ending -n pn the object makes it clear which is the subject and which the object, word order can be varied for stylistic or pragmatic purposes, very much more readily in Esperanto than in English.
Mi legas libron. – I'm reading a book.
Libron mi legas. – (A book is what I'm reading.)
Kio means "what", as subject of the sentence:
Kio estas tio? – What's that?
Kio estas sur la tablo? – What is on the table?
Where "what" is the object of the verb, the Esperanto equivalent is Kion: