Our word of the week literally means "a sack" or "bag" e.g. c'e' un sacco di patate sul tavolo, there's a sack of potatoes on the table. Easy enough.
But a very common colloquial meaning of the word is "a lot." Ha un sacco di soldi, he's got lots of money. C'erano un sacco di bambini alla festa. There were a lot of kids at the party.
Notice that when used in this informal sense the verb is plural if the noun following it is plural (and it usually is.) Un sacco di gente e' disoccupata- a lot of people are unemployed. Un sacco di donne fanno yoga- a lot of women do yoga.
(above, un sacco di soldi in the colloquial sense and un sacco di soldi in the literal sense.)
