Agreement After Expressions of Quantity

The subject (all, most, or some) can be singular or plural, depending on what follows the preposition of.
If the subject (all, most or some) refers to the singular noun, then the verb must be singular
If the subject (all, most or some) refers to the plural noun, then the verb must be plural

Ex. :
Most of the meal was delicious (singular)
Most of the meals were delicious (plural)
Most of the food was delicious (uncountable)

(all, most, some, half, part)-of the (object)-verb
When an expression of quantity using of is the subject, the verb agrees with the object