I agree with a comment from sumelic:
(The subject agrees with the verb.)
Since "Johnny" is the subject, the correct verb would be "is", not "are", even though that may not be immediately obvious.
What about these examples? See whether you can fill the gaps:
- The cars _______ (is/are) red.
- The colour of the cars _______ (is/are) red.
However, it is the meaning of the subject, not always the physical appearance of the word that helps us to decide whether to use a singular verb or a plural verb with the subject. (It means, the verb you should use in a sentence may change depending on what you mean by the subject.)
The audience is clapping. (taken as a unit)
The audience are clapping. (taken individually)
Here is another:
Our team has won the match.
Our team have won the match.
Our team are divided. (The members of our team are divided.)
Moreover, grammar is not always the same. Sometimes, when one country uses a singular verb, another country prefers a plural verb in its place. However, users may use it differently irrespective of the country they live. The subject is controversial, though.