learning grammar

There is a great sugestion to make multiple cards for learning grammar. For example, if you learn German, you create cards like "Ich gehe spazieren", "Er geht spazieren", "Wir gehen spazieren" etc. But in the app, when I tap at "Grammar", I can chose only one sentence for the word. So, I need to chose, if I'd like to learn the word only in a root form, in a root form+conjugated for single in present time or a root form+participle. Defenetely not enough! I think it shoud be possible to make a large amount of cards, using all the grammar forms of the word, otherwise I don't see how can it be possible to learn the language.