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Had zero fault, but the skill won't get gold..

I have this problem with my French tree:

Few days ago i was trying to strengthen a few skills, and some of them seemed to stay at the same level.. thought it was just a bug at the time. But I just took the test again (with zero wrong answers) and it stays the same.. at (4/5)

Any ideas how to fix it?

April 1, 2015



The strengthen button does not always return the skill to gold after one try. Sometimes it takes two or three attempts.


Even if all answers are correct?


Yes even if all answers are correct. If you count the number of words in a skill there are often about 60 plus words. Each strengthening exercise can only strengthen about 18 words max, so if all the words are very weak, it will not necessarily turn the skill gold again on the first try.

Of course, the actual algorithm is much more complex than that but you get the drift.


Good to know.. Thanks!


18 total words maybe....

But, duolingo only picks 8 (maybe 10) words from each skill to test at a time.


That is why I said 18 maximum.


Don't use the mouse-over hints unless you have to. Whenever you do, you are telling Duo that this is a word you don't know.


Do all the lessons in the skill.

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