1. which sentence contains an error in subject-verb agreement? elke or carina is going to be the new dance squad captain. july and august are the warmest months of the year. each volunteer and staff member need to arrive at the scheduled time. some of her friends and family members are coming over for dinner. which sentence contains an error in subject-verb agreement?

Each volunteer and staff member need to arrive at the scheduled time.

Explanation:

The adjective each is used before a singular countable noun, and, therefore, the verb should be singular, too.  

So the sentence should be written as "Each volunteer and staff member needs to arrive at the scheduled time."

All the other sentences contain no errors in subject-verb agreement.

explanation:

if you’re a fan of chocolate, every occasion is right for this treat. feeling down? eat some chocolate. celebrating? eat some more. want to show your valentine how special you think your sweetheart is? offer up chocolate!   people have been enjoying chocolate as a food, drink and medicine for thousands of years. the ancient maya and aztecs called chocolate kakaw and used it as medicine. they also made chocolate offerings to their gods. chocolate comes from the cacao (kuh-kow) tree, and its scientific name reflects its history. theobroma cacao translates to “cacao, food of the gods.” these days, chocolate is not just for deities. the treat has become popular around the world.

after i had a fight with my girlfriend, ben advised me to apologise.

explanation: