who is right?

#18 - Yes, that is the normal American interpretation, but my point is that British speakers also use the plural in a way that US speakers do not. "Ford are introducing ..." is common in British advertising but never seen in America.

#11 - what makes "A large percentage of the students IS immigrants" more technically correct than "A large percentage of the students ARE immigrants"? Vinnie's quote from the American Heritage Dictionary makes sense to me.

The "Chelsea/Ford" issue is a bit different. In this case the cup is held by Chelsea, the football club - the individual players are not cup holders. Similarly no individual Ford employee is launching a new model - the company as an entity is doing it. So the singular is logical in these examples (even though, as already noted, in Britain/Ireland the plural is often used). By contrast, in my example, it is the individual students that are immigrants.

heres the way in canada.

regarding the anaheim ducks hockey team:

the ducks ARE the cup holders.
Anaheim IS the cup holder.

but....
are anaheim the champs?
or
is anaheim the champ?

very confusing. furthering the need for revision of our ridiculous language.

Thank you all very much for your interesting replies!

I'll give the context of the discussion. Bf and I were talking about corruption in Chinese middle schools. Students have to take extremely diffucult entrance exams to go to 'the best schools'. I think that the original sentence was something like this:

'60% of the students is (are) very good, the others just pay a lot of cash and get in too. Bf was very abrupt in correcting me. I just said yes and wanted to hear other people's opinion, so that's why I asked you. Today he said that it does sound more natural to say 'are'.

Btw, I am Dutch and I remember reading a collumn by Kees van Kooten about the topic, he was upset about the frequent usage of 'are' when it should be is.

Did Kees van Kooten write about "is" vs. "are" in English or in Dutch? (And out of curiosity, was it Kees van Kooten or one of his countless alter egos "Prof. dr. E. I. Kipping, neerlandicus"?)

OP, you changed it in such a way that there's really no issue (in English, anyway). The votes for "a large percentage . . . is" were based on the facts that "a percentage" is grammatically the subject of the verb and is grammatically singular. But if you say "60% . . . are/is' there's no question that the answer is "are" (I don't really think there's a question even with the other, but not everyone agrees). Per cent = in a hundred. "Sixty [students] in a hundred of the students are very good."

#25 -- There is an issue for us Dutch speakers. In Dutch "procent" is a singular noun, and 60% is read as "60 procent"; the plural "procenten" is not used. Thus, "60% is is" (with the singular form of the verb) is the only correct form, no matter what kind of 60% (60% of children, 60% of the estate). It may not be entirely logical from an English speaker's point of view, but neither is "the police are" from a Dutch point of view. It is something that needs to be memorized as 'just the way it is'.

The word "percent" or the symbol "%" can be singular in English. For example, "60% of the cake is coated with chocolate icing." I don't think anyone would say "60% of the cake are ...". Similarly, "60% of the city is African-American" -- but, "60% of the people in the city are African-American."