This post was originally written as a response to multiple questions on the Duolingo forum. People were asking why they needed estas in a sentence if they already included ĉu. And so, this blog post is written from a Duolingo perspective. It also is more about what ĉu is NOT, rather than what it actually is.
If you need to know the basics about ĉu, have a look at this video from the Lernu kun Logano series. Otherwise, keep scrolling to find out all the things that ĉu is NOT.
Ĉu is not Estas
This question came up a lot on the Duolingo forum. I’ve seen it a lot in over 21 years of teaching Esperanto by email – but it seems that the inductive “grammar free” approach of Duolingo has deepend the confusion. I now see a question like this several times per week.
Given the sentence and translation:
- Is bread brown?
- Ĉu pano estas bruna?
A learner asks – Why do I need estas if I already put ĉu?
When you see all sorts of questions starting with “is” and the translation starts with ĉu, it’s reasonable to conclude that ĉu actually means “is” — but it doesn’t. Estas means is. If your sentence has “is” in it, it needs estas
So what is ĉu then?
Ĉu turns a statement into a yes/no question (or and either/or question.)
Statement:
- Pano estas bruna
- Bread is brown
Question:
- Ĉu pano estas bruna?
- Is bread brown?
Ĉu is not Do
Another common mistake is to think that ĉu means “do”. Consider:
- Do you have money?
- Ĉu vi havas monon?
It would be natural since vi, havas and monon means “you”, “have”, and “money” – that ĉu means “do” – but it doesn’t. Again, it just turns a statement into a question.
Statement:
- Vi havas monon.
- You have money.
Question:
- Ĉu vi havas monon?
- Do you have money?
The problem becomes more obvious when we want to ask a question like:
- How much money do you have?
- Kiom da mono vi havas?
For some people it’s tempting to throw ĉu in there – but kiom is already the question word and you don’t need another.
Ĉu does not change the word order of a sentence
It’s very tempting when translating a sentence like “Is bread brown?” by copying the word order you see in English.
- Is bread brown?
- Ĉu pano estas bruna?
A learner asks – can I say: Ĉu estas pano bruna?
No, you can’t. Word order matters in Esperanto, and remember that “ĉu” changes a statement into a question. Remove “ĉu” and you get the statement back.
- Ĉu estas pano bruna?
becomes
- Estas pano bruna = There is brown bread.
Which means
- Ĉu estas pano bruna? = Is there brown bread?
I thought Ĉu was only for yes/no questions!
Originally, the Duolingo Tips and Notes said that ĉu was for yes/no questions. Then for a while they changed it to “yes/no or either/or questions.” Apparently they changed it back.
It’s basically used in for the kind of closed questions that we make in English by changing the order of the subject and verb.
- Is it a dog?
- Is it a dog or a cat?
- Is it a dog, a cat, or a mouse?
The first is a yes/no question. The second is probably an either/or question. The third is a multiple choice question. You can think of it as a series of yes/no questions, if you want.
- Is it a dog (yes/no), a cat (yes/no), or a mouse (yes/no)?
While we’re here – Why don’t we put an -n on the words after estas?
Briefly, because when I say Mi estas alta – I’m not doing anything to alta, I’m saying that alta is a quality that describes me. When I say Mi estas Tomaso, I’m not doing anything to Tomaso. I’m saying that Tomaso and “mi” are the same person. When I say Mi estas instruisto, I’m not doing anything to the teacher, I’m saying that “teacher” is a category that I belong to.
This is yet another case where word order matters in Esperanto.
Duolingo added an -s to my adjective
… but it didn’t make me add estas.
Yes, this is another way that Duolingo can be confusing. What happens is that you’re given a sentence to translate such as the following:
- Is it good?
The correct answer, with estas and ĉu would be:
- Ĉu ĝi estas bona?
But if you forget to add estas (because Duolingo didn’t tell you that ĉu is not “is”), you might be tempted to try:
- ❌ Ĉu ĝi bona?
At this point Duolingo has to guess what you’re trying to say and it doesn’t give you the BEST answer at this point. It gives you the answer it THINKS you were trying to type. In this case, it sees you didn’t include a verb (estas) and guesses that you wanted to use the verb bonas here.
By the way, if you’d like know why the preferred answer is the one with estas bona and not bonas, I wrote a blog post about that over on Transparent Language.
Do you have more questions about how ĉu works?
I’d love to hear from you.
Of course you can leave a comment here on the blog below. However, the best way to get regular hints, tips, and mini-lessons is to join my mailing list. <- Click the link and enter your email address to get periodic updates, answers to questions you or other learners are asking, and information about other opportunities to improve your Esperanto.