Learn Italian: Mi è piaciuta moltissimo l'atmosfera della festa. - I really liked the atmosphere of the party.

In Italian, the verb piacere works backward compared to English. The thing you like is actually the subject of the sentence doing the 'pleasing.' Since the atmosphere (l'atmosfera) is a feminine singular noun, the past tense verb must match its gender and number, becoming è piaciuta. Literally, this sentence means 'The atmosphere of the party was very pleasing to me.'

What does the word moltissimo mean, and how is it formed?

Moltissimo means 'very much' or 'a whole lot.' In Italian, you can add the ending -issimo to many adjectives and adverbs to make them much stronger. Here, it takes the word molto (a lot) and turns it into an extreme to show you really loved the atmosphere.

Why does moltissimo come before l'atmosfera instead of at the end of the sentence?

Adverbs like moltissimo usually go right after the verb they modify (in this case, è piaciuta). Italian is quite flexible with word order, and keeping the verb and its adverb together before introducing the subject (l'atmosfera) sounds very natural and emphasizes how much you liked it.

Why do we use della festa instead of just di festa?