Singular subject and singular verb:
  • My uncle has bushy eyebrows.
  • She eats a lot of Belgian chocolate.
Plural subject and plural verb:
  • They run down the road.
  • The children have very loving parents.
 

The verb agrees with the subject and NOT with the noun next to it.

Correct: Her bouquet of flowers is a birthday present.

Incorrect: Her bouquet of flowers are a birthday present.

(The subject here is bouquet, which is part of the noun phrase bouquet of flowers. Since bouquet is a singular item, and we are referring to it and not the flowers, a singular verb should be used.)
 

More examples

  • Correct: The man with two briefcases is heading for the airport.
  • Incorrect: The man with two briefcases are heading for the airport.
  • Correct: The instruction to the boys was not clear.
  • Incorrect: The instruction to the boys were not clear.
  • Correct: The thieves who stole the money have escaped.
  • Incorrect: The thieves who stole the money has escaped.
  • Correct: The cost of goods has gone up.
  • Incorrect: The cost of goods have gone up.
  • Correct: One of the leaders is a female.
  • Incorrect: One of the leaders are a female.