A few weeks ago I heard a flight attendant announce that airline policy “requires that all window shades are open during takeoff.”

Back in my youth, which still seems not all that long ago, I would have expected to hear that the policy requires that shades be open during takeoff. Alas, reports of the death of the subjunctive mood in English are not so exaggerated.

Don’t worry, I’m not devoting this column to nitpicking English grammar. But that experience got me thinking about the general subject of what are called verbal moods (or sometimes modes), and the fact that many Esperanto speakers, notably those who come from an English language background, have trouble with them. Today’s schools often ignore the subject (and it doesn’t help that the term subjunctive in English is applied to two different moods, thus making it harder than it needs to be).

So just what is a mood in the context of verbs? The easiest way to explain is by example.

The most common mood, in Esperanto and in English, is the indicative, so called because we use it to indicate something: Leono estas besto. La unua Universala Kongreso okazis en 1905. Venontjare Esperanto-USA kongresos en Berklio. The tense endings -is, -as, and -os are the endings of the indicative mood. This is probably the easiest mood to understand because it’s so basic. Students do make mistakes with it, for example using the wrong tense (often caused by interference from their native language), but past the beginner level they rarely misuse the indicative mood except by using it when they should be using something else.

Another mood familiar even to beginners is the infinitive, marked by the ending -i. The infinitive is used almost like a noun, so we can say, for example, “Mi volas manĝi” as we would say, “Mi volas manĝaĵon”. There are two rules that help students avoid mistakes:

1. When two verbs come together, the second one should be an infinitive. (We wouldn’t say *“Mi volas manĝas.”)

2. An infinitive can never serve as the main verb of a clause.

The two remaining moods are the ones that give more trouble: the conditional and the imperative.

The ending -us marks verbs in the conditional mood, which despite the name is actually used to convey that something is unlikely. Consider the following two sentences. Which of them is grammatically correct?

• Se vi estos tie, ankaŭ mi estos tie.
• Se vi estus tie, ankaŭ mi estus tie.

The answer is, “It depends on what you’re trying to say.” Both are “conditional” in some sense, but the first would be used to speak of something deemed likely and the second to convey doubt. This might be clearer if we expand the first example into a bit of dialog:

Li: Ĉu vi estos ĉe la festeto? Mi estos tie.
Ŝi: Se vi estos tie, ankaŭ mi estos.

Here’s the equivalent in English:

He: Are you going to be at the party? I’ll be there.
She: If you’re going to be there, I will too.

Now consider this somewhat different conversation in both languages:

He: I won’t be at the party. I wouldn’t enjoy it.
She: If you were to change your plans, I would go.

Li: Mi ne estos ĉe la festeto. Mi ne ĝuus ĝin.
Ŝi: Se vi ŝanĝus vian planon, mi irus.

In the latter bit of dialog, except for the very first assertion (“Mi ne estos ĉe la festeto”) the speakers are referring to something that’s either doubtful by itself or else conditional on something unexpected or doubtful.

The distinction is a bit subtle but useful for conveying information.

The conditional is also employed in both English and Esperanto as a way to express a polite request. “Mi volus kafon” (“I’d like coffee”) is less insistent than “Mi volas kafon” (“I want coffee.”)

Another convention is to use the verb devi in the conditional mood (devus) to express an obligation or something we ought to do, as in “Mi devus ĉeesti la kunsidon” (“I should attend the meeting.”)

Since the conditional mood has in itself no way to express tense, saying something like “I should have attended the meeting” requires more than one word (as it does in English, for that matter), as for example, “Mi estus devinta ĉeesti la kunvenon.” A variant that is sometimes used, and is a logical extension of the usual grammar of Esperanto, is “Mi devintus ĉeesti la kunvenon.” After all, the participle devinta is technically an adjective, and Esperanto allows us to form so-called stative verbs from adjectives: “Vi belas”, for example, in place of “Vi estas bela.”

Whether to teach your students about such not-quite-standard constructions is up to you, but there’s a lot to be said for the conventional advice of teaching them to recognize what devintus means in case they run across it, but at the same time discouraging them from using it themselves until they have become more familiar with the language.

Now we come to the -u ending, which Esperanto uses for the imperative. Native English speakers have no problem employing -u in the second person in a simple sentence, as in “Iru for!” or “Silentu!” because that’s how the imperative is used in English. A little harder to get our minds around is a first- or third-person imperative such as as “Ni komencu la kunsidon” or “Ĉiuj kantu”. The closest English equivalent is a construction with the verb let: “Let’s start the meeting” or “Let everyone sing.”

It’s helpful here to point out to students that the imperative is really an expression, a wish, or an opinion that something should be done. “Iru for!” conveys the message “I want you to go away” or “You should go away.” Likewise, “Ni komencu” and “Ĉiuj kantu” can mean “We should start the meeting,” or “I want everyone to sing.” In fact, the Esperanto ending -u is often called the volitive, related to the verb voli.

It’s in subordinate clauses where we’re most apt to use the indicative when we should be using the imperative. A student who wants to say “I insist that he come tomorrow” may well say, “Mi insistas, ke li venos morgaŭ” (or even worse, “… ke li venas morgaŭ.”) But the indicative mood indicates something, so “Mi insistas, ke li venos morgaŭ” would mean something like “I insist that it’s a fact that he will come tomorrow.” If the speaker is trying to express a demand rather than am emphatic prediction, what he or she ought to say is “Mi insistas, ke li venu morgaŭ.”

You might also point out in passing that in English, the corresponding expression is “I insist that he come tomorrow.” Some students might suppose that he comes is correct, because that’s how they learned the indicative mood in school, and school didn’t bother to teach them very much about other moods. The rule is that where Esperanto uses -u, English generally uses the form of the bare infinitive, as in “… that the window shades be open …”. A bit confusingly, gurus of English grammar call this mood the “jussive” or the “jussive form of the subjunctive.” It’s probably safe to say that most English speakers have never heard of the jussive and it’s just as well.

Which brings up another point. Do we want to hit students with technical terms like mood and indicative? I’d say it depends on the students and their backgrounds. There’s nothing wrong with simply talking about how to use the verb endings without naming the corresponding moods. On the other hand, if students happen to know enough grammatical terminology already, there’s no harm in using it and it might help to make things clear.

A final note: It’s useful to remind students that we’re not talking about arbitrary rules like those that govern a card game but rather tools for conveying meaning. We use tenses and moods to better get across exactly what we’re trying to say.