Quiz: Writing for business — have or has

Which is correct?

Each of you _____ contributed a great deal to the success of this project.
a. have
b. has

Correct answer: b

Explanation
The subject of the sentence is the pronoun each. Each is singular and requires the singular verb has.

Many people mistakenly choose the verb have to match the word you, but you is part of the prepositional phrase of you and therefore you cannot be the subject.