"My little sister likes running."

Translation: 妹は走るのが好きです。

[kezzoa]

What does the の add to the sentence?

[Paralars1]

added to verbs (はしる) for nominalization. It turns to run into a pseudo noun running

[3Rton]

Does this work with all verbs?

[Raphazilla]

Why wont it accept most of these "likes" exercises without the ?です at the end?

[No--One]

好き is used as a noun here. If it were an adjective (i-adjective), です/だ wouldn't be required, but since it's a noun, it needs a copula to link it to "走るの".

[CharlesKelly86]

A lot of the lessons keep putting わたしの in front of brothers and sisters. Of course Duolingo marks it wrong to use わたしの this time...

[_Othique_]

妹は走るのが好きです。

[Lazer2903]

妹は走っているのが好きです Is not allowed?