Verbs are important building blocks of most (if not all) human languages. They usually describe either actions or states of being, but they can also carry additional information about the subject of the sentence, when the action takes place, and so on. For example, the English verb “moves” expresses not only an action of movement but also that the action is being done by a third person. Similarly, the verb “looked” (as opposed to “look”) tells us that the action took place in the past.
If you have ever tried to learn Spanish or French, you know that learning all the different forms (for different tenses and persons) can be a daunting task—a single verb in Spanish can have more than 60 different forms!
Mastering the system of verbs in a language like Spanish often requires many years of practice. In Esperanto, you can literally do the same in about 5 to 10 minutes, which is approximately the time needed to read this article.
The infinitive: -i
There are two types of infinitives in English: We either use the verb itself, as in “he helped me do it”, or we put the word “to” in front of it, as in “It is important to do it”, and some verbs cannot form the infinitive at all (we cannot say “to can” or “to must”).
In Esperanto, no matter what the verb expresses, the infinitive is always formed by adding the suffix -i to the root of the verb. Here are a few examples:
lerni | – | to learn |
havi | – | to have |
sendi | – | to send |
helpi | – | to help |
esti | – | to be |
(I have intentionally chosen verbs that look similar in Esperanto and in English so that we can discuss grammar points without having to worry about vocabulary, with the exception of esti (to be), which is too important to ignore.)
The present tense: -as
To form the present tense of a verb in Esperanto, simply replace -i in the infinitive by -as. For example, the present tense of lerni (“to learn”) is lernas:
mi lernas | – | I learn |
vi lernas | – | you learn |
li/ŝi/ĝi lernas | – | he/she/it learns |
ni lernas | – | we learn |
vi lernas | – | you (all) learn |
ili lernas | – | they learn |
Esperanto (like English and unlike Spanish or French) distinguishes neither between the second person singular and plural nor between informal and formal “you”, so the English pronoun “you” can always be translated simply as “vi”.
The nice thing is that there are no exceptions to the “-i → -as” pattern, not even the verb “to be”:
mi estas | – | I am |
vi estas | – | you are |
li/ŝi/ĝi estas | – | he/she/it is |
Here are a few example sentences:
I don’t have water. Ŝi estas bela.
She is beautiful.
And how do you form the present progressive tense, e.g. “I am learning”? The answer is, you don’t have to. The -as tense already includes the idea of anything that happens or is happening in the present, so “mi lernas” can mean either “I learn” or “I am learning”, depending on the context.
The past tense: -is
The past tense is a nightmare of many a language learner. Even in English, which otherwise has a relatively regular grammar, there are hundreds of verbs with irregular past-tense forms: go – went, is – was, catch – caught… To form the past tense of a verb in Esperanto, simply replace -i by -is, as in
mi lernis | – | I learned |
vi estis | – | you were |
li havis | – | he had |
ni sendis | – | we sent |
ili helpis | – | they helped |
A couple of example sentences:
She sent the letter. Ni havis bieron.
We had a beer.
The future tense: -os
By now, it shouldn’t be surprising that the future tense is formed simply by replacing -i by a different suffix, and that suffix is -os:
mi lernos | – | I will learn |
ŝi helpos | – | she will help |
For example:
She will not help me. Vi lernos Esperanton.
You will learn Esperanto.
The expression “going to” is usually preferred to “will” in English when the action is imminent. In Esperanto, you can simply use -os in both cases:
The bomb is going to explode!
The conditional: -us
The conditional mood is as easy to form in English as it is in Esperanto. Instead of putting “would” in front of the verb, we replace the ending -i by -us, and the resulting verb is used in almost the same way as in English.
For example, ŝati means “to like”. To say “would like”, replace -i by -us:
I would like to learn Esperanto.
However, the most common use of the conditional is to form conditional sentences. In English, we use the so-called subjunctive mood after “if”, and the conditional mood in the main clause, e.g. “if he were here, he would get the job”. In Esperanto, you don’t have to think about which clause is which—you just use the -us form in both:
If you helped me, I would learn faster.
The imperative: -u
The only case we haven’t covered so far is how to give commands in Esperanto. In English, the command form (the imperative mood) is always the same as the infinitive: “Be there or be square!”, “Go away!”, “Give me that!” To form the imperative in Esperanto, replace -i by -u:
Learn Esperanto! Helpu min!
Help me!
One significant difference is that, since the imperative in Esperanto is clearly distinguished from other forms, we can use it to give commands to any person, not just “you”. In English, expressing such commands is more complex (and the result may sound rather stilted):
mi lernu! | – | let me learn; I shall learn |
(vi) lernu! | – | learn! |
li lernu! | – | let him learn; he shall learn |
ni lernu! | – | let us learn; we shall learn |
ili lernu! | – | let them learn; they shall learn |
The suffix -u is also used in indirect commands in the same way as the command form is used in formal English:
It is necessary that he be there.
Summary
The tenses described above cover the vast majority of verb forms you will meet in practice in Esperanto. What we have not learned so far is how to form participles (words like “doing” and “done”), and I will discuss those in a separate article. However, participles are much less commonly used in Esperanto than in English; while it is possible to literally say, for example, “I am learning” (mi estas lernanta), using the simple -as form is much more common.
To sum up, let’s take a look at all the forms we have learned in this article one more time:
esti | – | to be |
estas | – | am/are/is |
estis | – | was/were |
estos | – | will be |
estus | – | would be or were (in conditional clauses) |
estu! | – | be! |