If it's new, is underlined and highlighted. Click on it, and it'll tell you the translation. If is relatively new, it'll be underlined, but not highlighted. Click on it and it'll show the translation. Once you've seen it a few times, iit's no longer underlined - and you can't click it to translate before answering.
Thats not what happening for me im getting new worfs that ive never seen not underlined and highlighted. So i cant click on the word to find the answer. Which makes it a lot harder even when writing all the words down.