Interface doesn't work well

After each sentence, i can not click on "Check" (it is not green). I need to click on "Don't know the answer?", after that the button "Continue" is green and i can click on this button. After that, i can go one with the next sentence. But the sentence may be wrong, Duolingo find it always correct. Also i can go with the mouse over the sentence that needs a translation, but i don't get the suggestions for the different words. This is not the first time that i had this problem. I work with windows 7 and Safari

November 11, 2013


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