Sometimes I do not understand, why absence of article 'die' in front of the Mädchen mean the word is plural. Why answer "I like girl" doesn't count?
It's the same in English. If the singular and plural are identical, no article means plural.
I like sheep.
They hunt deer.
Whales eat fish.
Even if you disregard the plural, 'i like girl' would be 'i like the girl' in english. Anyway, Mädchen without article is plural, for one girl, you would either need the definite (das) or indefinite (ein) article.
Thanks! (I did not even know such rule for English, looks like I need duolingo for English)