(Pronoun Agreement Error) The cafeteria was in an uproar because every student was overcharged for their lunch.

NEW SENTENCE:
The cafeteria was in an uproar because students were overcharged for their lunches

The new sentence is correct if you put a period at the end of it.

To correct the pronoun agreement error in the original sentence, we need to ensure that the pronoun matches the noun it is referring to in number and gender. In this case, the noun is "students," which is plural, but the pronoun "their" is singular.

To fix this error, we can change "their" to "their lunches," which maintains the plural form and ensures agreement with the noun.

The revised sentence is: "The cafeteria was in an uproar because students were overcharged for their lunches."