It happens only to phrases.
OK, thanks for the confirmation! If you run into other issues on the lesson page be sure to let us know!
New bug. When you click on the blue word and then on offered hints - nothing happens. Actually a hint is added, the word now is yellow, but cursor doesn’t move forward. You can basically click on hint million times and just earn free coins. Please fix this, because instead of learning I’m just clicking to earn coins 
Sorry for the trouble, this should now be fixed. Let us know if you run into any other issues!