Quality control

I went through 50 “por vs para” examples with my Spanish teacher. They found 3 mistakes. That error rate is awful, and suggests that no one has ever been through the set before.

What quality control does this site have?

Please read the FAQ page. Most of the sentences are sourced from an external corpus Tatoeba.org where everyone including non-native speakers can post example sentences and translations. Most of them are not peer-reviewed. Clozemaster is not responsible for the quality. As a pro user, you can push the “ignore” button if you don’t like, or “edit” the translation. You need to report directly to Tatoeba if you really want to improve sentences. You can find the “source” button (link to Tatoeba’s sentence ID) on the right bottom side of each lesson page after you answer.

You said “that error rate is awful” by finding only 3 errors out of 50 examples. It’s not that bad at all, indeed. As a Japanese native speaker, I found one fourth (25%) have critical errors in the Japanese sentences. If including minor errors, the rate is around 30%.


Thanks for the post and sorry for the trouble! What mistakes did you come across? @MsFixer is indeed correct that sentences are sourced from Tatoeba, and given the massive number of sentences, we can’t yet realistically moderate them all.

We do, however, have a growing team of moderators working to respond to reported sentences. You can report a sentence by clicking or tapping the button with a flag icon bottom right after answering, and we’ll get it fixed as soon as possible.


If you find an error, the best thing to do is to report to Clozemaster and to Tatoeba. As far as I know, Clozemaster does not pass on reports of errors to Tatoeba, nor does it check sentences in its current collection against the ones at Tatoeba. I have seen that many sentences/translations containing errors at Clozemaster have already been corrected at Tatoeba since the time that Clozemaster imported the sentences, but many have not.


given the massive number of sentences, we can’t yet realistically moderate them all.

But, frankly, what do I pay you for? I didn’t come here to learn possibly incorrect sentences, neither did anyone else.

a growing team of moderators working to respond to reported sentences

And how, exactly, is a language-learner meant to determine if the sentence is incorrect or merely idiomatic? How many years will it take before all the bad sentences are removed? Even @MsFixer who bizarrely seems to be defending you admits that “one fourth (25%) have critical errors” - how can you possibly say your site is useful for learning Japanese?

Thanks for the reply! We certainly don’t mean to be a source of frustration and we’re happy to provide a refund if you’d like - just kindly email hello@clozemaster.com.

With 3 mistakes out of 50, assuming they are indeed mistakes, that still means 94% were correct. What’s the category of mistake you’re referring to? In the sentences themselves, the translations, or something else?

No ones comes here to learn possibly incorrect sentences of course, but we look at the occasional mistake worth the benefit of being able to play through thousands, if not hundreds of thousands, of correct sentences in your target language. Even Duolingo, with $183M in funding, still has a report button.

We try to provide as many resources as possible - click or tap a word or select all or part of a sentence after answering to get a machine translation from Google, easily check a number of dictionary links, or search other sentences on Clozemaster. You can also post sentences questions to the forum to get input from other users, including users like @MsFixer who are kind enough to help with their native language, and as mentioned above you can report the sentence if you’re unsure to have it checked by our moderator team. We’re working to make more resources available, and we’re open to ideas and suggestions as well.

We try to make corrections in Tatoeba as well when possible, though you are correct that we don’t yet pull in updates to individual sentences in a timely manner.


Thank you @mike and @alanf for your follow-up comments :slight_smile:

I would like to explain to @Chipperton345 why some Clozemaster users are willing to subscribe the PRO despite the poor quality of Tatoeba sentences.

It’s the same as Twitter v. the Wall Street Journal (or social media v. “quality newspapers”). Some WSJ subscribers see that Twitter merely contaminates their minds and is just a waste of their precious time. Some Twitter users, however, are fully aware of so many falsehoods on Twitter. They love to debunk falsehoods, and even believe that expressing their counterarguments is actually a great part of their own learning process – debunking requires them to proactively look for additional explanations based on facts and reliable sources. And it makes them more humble because they also know that they may make mistakes themselves.

Clozemaster is like Twitter where the content is socially developed. If I use only traditional resources such as a language school or printed textbooks, they are probably as safe as reading WSJ. But it also makes me a passive learner. I pay for the fee of “improving by myself”. The Clozemaster PRO functions enable me to correct mistranslations by myself, to express my different opinions on the forums, to learn from others, and to create my own sentence collections with TTS (text-to-speech; audio).

Those functions are superior to a flashcard app Anki, for example. I’ve never been a paid user on Duolingo where unpopular courses (like my Indonesian from English) are almost abandoned (i.e. user reports are completely ignored for years), and users cannot move on until they enter “improper” answers. Clozemaster allows me to skip such improper ones by clicking the “ignore” button, to add alternative answers, or to edit the translations. It’s less stressful.

I occasionally take questions from Japanese learners here on Clozemaster. It’s not because I am kind enough :stuck_out_tongue_winking_eye:, but explaining grammar and vocab of my native language also improves my foreign language skills. In short, “teaching is learning”.

Before cancelling your subscription, please figure out which type you are: a self-driven Twitter user or a typical WSJ subscriber. Clozemaster is not a one-size-fits-all solution.


What’s the category of mistake you’re referring to? In the sentences themselves, the translations, or something else?

@mike - “por vs para” is a common topic in English->Spanish learning as they are both often translated into English as “for”, and Clozemaster provides a course to help you practise. There were several categories of error:

  • Incorrect Spanish - “para” instead of “por” (there were 3/50 of these)
  • Incorrect English translation
  • Ambiguous given the English translation (but only one is accepted)
  • A word other than “para” or “por” would be better.

See my recent forum discussions for these. I don’t know about the credentials of the other users but these were pointed out to me by my Spanish teacher.

we look at the occasional mistake worth the benefit of being able to play through thousands, if not hundreds of thousands, of correct sentences

This seems a bit disingenuous given we’re talking about an error rate of 1 in 16 for this course, and apparently 1 in 4 for Japanese.

I hate to break it to you, @MsFixer, but @mike is going to do all he can to remove the mistakes and turn this site into WSJ. Without the constant noise of unreliable translations, you will be forced to passively learn from quality content. I hope this does not discourage you from your journey of learning Indonesian.

Thanks for the reply!

I’ve looked through your entire post history and was quite impressed with the quantity and quality of the responses you’ve received from the community! Kudos to everyone here :slight_smile: :beers:

I also saw what you mean about some of the translations being perhaps a bit ambiguous, and an instance where que would likely be a better fit than por or para, but I didn’t see any issues that were that glaring. If there were others that you recall, or you notice others, please feel free to report them of course like I mentioned above and we’ll aim to get them fixed as soon as possible.

What it comes down to, I think, is that everyone learns in their own way. For some people, the crowd-sourced content and occasional ambiguity or mistake is ok and Clozemaster is really good fit. For others, it’s not a good fit, and that’s ok too. If you’re finding yourself in the latter camp, simply let us know and we’ll get you refunded so you can move on to other resources that might be a better fit. :slight_smile:

I’m not sure what’s up with this comment or where you’re getting your information on what I’ll do :slight_smile: but similar to what I mentioned above, we’re always working to improve the content on Clozemaster. That said, content will likely continue to be more analogous to Twitter than the WSJ :slight_smile:


I’m pro and have no complaints. Errors? They give us something to discuss with one another, and I get a mass of learning, practice and grammar for my subscription. Just saying…

Spanish Translation


There is nothing left.