I learned "finden gern" in high school and college to mean "like". This is confusing.
I, as a non-native speaker, would translate "like" in two different ways: "I like to ski" - "Ich fahre gern schi". And "I like skiing" - "Ich mag Schifahren" where the verb is "mögen" and "Schifahren" is a noun. And I only know about phrase "finden gut". An example: "Ich finde Schifahren gut" which I would translate as "Skiing is good in my oppinion."
Gloss over the word next time, and choose the option to conjugate.
I myself just too a screenshot of the conjugation to be used as a quick-card reference. Printing it could be a good idea, too.
Which is the good website or good book to learn more about verb forms? Duolingo sadly does not give any explanation on the grammar aspect.
German in Review by Kimberly Sparks is a good grammar book. It can be pricy, so look for a used copy. Practice Makes Perfect is another good workbook series. The plastic grammar cards available at big bookstores can be pretty helpful. They are a couple sheets that fold up and often have all of the major grammar points in one place. I have been using Conjugemos for Spanish and it is pretty helpful. http://conjuguemos.com/list.php?&division=verbs&language=german
The voice isnt picking up what i say a lot, i say the same thing 3 times and it only picks it up on the 3rd or 2nd time