There's this advice here, but you'll need a PhD in Rhetoric to apply the rules, and then there's this quick 'n easy guide from MT State University:
Originally Posted by shoaib 1
The words "number," "variety" and "majority" can be singular or plural, depending on whether they're preceded by "a" or "the."
But it doesn't tell us why "a majority" always takes a plural verb, and that bugs me. I'd like to know. And, finally, there's this very insightful, yet not very helpful article.
- A number are, but the number is.
- A variety are, but the variety is.
- A majority are, but the majority is.