This company has free online quizzes for German, Italian, Spanish, French, Chinese, Arabic, Russian, and English. 

Try one! They’re fun.

Although I haven’t tested all of them, the ones I have taken struck me as very professionally constructed.

I did have logistical trouble with the Arabic quiz, though; the font for the answers to the multiple-choice questions was so small I couldn’t read it. Then, when I changed the font size, there were resolution problems and I still had trouble reading it.  

Russian and languages with Roman characters were not a problem. As of the writing of this review, I hadn’t yet tried the Chinese.