"The fly is an insect."
Translation:La muŝo estas insekto.
Because PMEG and Zamenhof advise against it. I've answered this in detail in many other threads and on Esperanto Stack Exchange.
Feel free to seek out those answers and ask for more details if you need them. Given your history of reflexively disagreeing with me, I really can't spend a lot of time spelling out the answer again. If anybody else is curious, I hope they'll let me know.
The way it was explained to me, verbing adjectives is not perfectly synonymous with "esti [adjective]".
esti [adjective] means exactly what it sounds like: A thing can be described a certain way.
But verbing an adjective is (to coin a phrase) an anti-habitual. It means a thing isn't usually this way, but it happens to be so right now.
For example, you usually make green cookies. Via kuketoj estas verdaj. But today, you made red cookies for some reason. Via kuketoj ruĝas.
EDIT, 11 months later:
Whoever explained it this way is wrong, apparently. It seems that the difference between "ŝi estas bela" and "ŝi belas" is closer to "she is beautiful" vs "she radiates beauty". Verbing adjectives is either for poetic use only, or says that the thing is actively giving off those qualities. "Ĝi estas varma" is "it is warm", but "Ĝi varmas" is more like "it gives off heat". I'm still not 100% solid on this, but I think this is a lot closer to how it actually works.
However, I do reserve the option to have an "anti-habitual" in my own conlang, because it's a nifty idea.
Yep! La botelo estis malplena. Nun La botelo plenigas. Poste la botelo estos plena.
In the second sentence the bottle is changing state/going towards a state. Of course you have to add the appropriate suffix too.
I am not saying that malplenis and plenos is wrong, but i prefer estis malplena and estos plena over them.
To expand on what salivanto said:
There are two main categories of verb: active verbs and stative verbs.
Active verbs describe activities. Somebody does something, or somebody does something to someone or something.
If the action has no recipient, it is intransitive: She sleeps. He walks.
If the action has a recipient, it is transitive: She throws a ball. He washes the dishes.
It is the recipient of the action that is the direct object of the verb. In languages that mark this, they take the accusative case. In Esperanto, this is the function of the -n suffix.* What is thrown? What is washed? If you can re-cast the sentence into the passive voice, the verb is transitive.
Stative verbs, on the other hand, describe states of being. Somebody is something. Something seems a certain way. These verbs take a subject complement. In most languages, this is the nominative case to match the subject, because it describes the subject.
*In Esperanto, the -n suffix can also denote movement after a preposition:
Li saltas sur la tablo = He jumps on the table
He stands on the table and jumps up and down.
Li saltas sur la tablon = He jumps onto the table
He stands somewhere, jumps, and lands on the table.
Short answer: "No -n with estas."
Medium answer: When you're using estas there will be no -n after it because unlike many other verbs, estas doesn't do anything to anything. Rather, it's a bit like an equals sign that says that two nouns are the same thing, in the same category, or that a thing has certain qualities.
Long answer (Which I wrote elsewhere in reply to a specific but similar question):
The -n marker is for objects, not subjects. The reason there is no -n on "interkona vespero" is that "interkona vespero" is the subject.
- The interkona vespero is when?
The reason we don't use -n with estas is that estas doesn't ever have a direct object. I like to use the description that it's like an equals sign, however it's not really reversible.
- Mi estas Tomaso - Tomaso estas mi.
That works in reverse, but this one does not.
- Mi estas patro - Patro estas mi.
- Tomaso estas alta.
- Alta estas Tomaso
The way to look at it is that the words that come after "estas" are the same as the subject, or describe the subject in some way by showing that the subject is part of a category or has certain qualities.
I'm kind of easy to find. :-)
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