What is the subject of the sentence?

All of the stone masons working on the cathedral (is, are) residents of Harlem.]]> Is the subject sentence singular or plural?

All of the stone masons working on the cathedral (is, are) residents of Harlem.]]> All of the stone masons working on the cathedral are residents of Harlem. Type the correct form of the words in parentheses into the box, then submit it and say the sentence.

All of the stone masons working on the cathedral (is, are) residents of Harlem.]]>