Is the sentence correct?

I can't see anything wrong with it.

Me neither. Didn't your friend indicate where the problem might be?

Unless it is necessary to shift tenses, your verb tenses should be consistent:

The driver took the people who were waiting for a ride.

Took and were are both past tense; had been is past perfect tense.

The driver took the people who had been waiting for a ride.

That's a fiction, Debra. There is no actual Sequence of Tenses/Concord of Tenses rule in the English language. [The Cambridge Grammar of the English Language]

In fact, doesn't this usage here follow perfectly in line with the usual stated reason for using the past perfect, ie. to describe an action that occurred earlier than a later action.

the prosecution rests

I understand that you do not tolerate "rules" for writing, but I don't mind them. For instance, I like parallel construction and verb tense consistency.

Both phrases about people who "were waiting" and "had been waiting" convey a waiting activity that occurred prior to the time the driver "took" the people. It was not necessary to shift tense to convey the message. However, if you enjoy shifting verb tenses when it's not necessary to do so, then go for it.

Even if I agreed with you, Deb (and I'm not sure whether I do or don't), there is nothing wrong with the sentence as presented that would make me, as a prescriptive-minded English teacher, wish to correct it.

That's simply not true, Debra. I, and if you'll note, the CGEL and the rest of language science, don't agree with rules that aren't rules. "liking" parallel construction and verb tense consistency does not a rule make. That sort of a position describes a style preference but again, preferences do not create rules.



There can't have been any tense shift because the past perfect is not a tense, it's an aspect.

You're much more intelligent than that, Merry.

He just told me that the sentence is ambiguous. Asked for the reason, he said he could not quite make out what his teacher said.

I can't see any ambiguity but that doesn't mean that there couldn't be some for some people. An isolated sentence can have different meanings to different people. Thankfully, language doesn't operate in a vacuum.

Why not ask him to ask his teacher to explain it once more? That's what teachers are there for, to help clear up students' puzzlement.

Yes. In casual conversational BrE certainly, to be "taken for a ride" can mean to be tricked or defrauded, and a native English speaker might well avoid the phrase for that reason.

If you say so... AND Sarah Palin can't have quit her job because resigning isn't quitting, it is an aspect of not quitting, ALSO. You betcha! With incoherency becoming the norm, the next descriptivist manual of the English Language ought to be a doozy.

I see the possible ambiguity as follows.
The driver took the people who had been waiting for a ride.
They hadn't necessarily been waiting for a ride.

The driver took the people who had been waiting for a ride.
They had been waiting for a ride and he took them.

"manuals" are for prescription, Debra. They usually consist of one skinny little book or one skinny little chapter in some book. They repeat the same tired old pieces of folklore that have been repeated for hundreds of years.

Go down to your local library, Debra, and compare a prescriptive manual with, say, The Cambridge Grammar of the English Language or Longman Grammar of Spoken and Written English.

Read just a few pages and you'll quickly notice that it's like comparing Ican on Constitutional Law to that of any top notch legal scholar.

In your example above, you're confusing the nuances inherent in vocabulary, which I'm sure you'd agree exist, with the mechanical structures of language.

Let's stick with your terminology and call the past perfect a tense. That still doesn't make your argument work, for we mix "tenses" all the time.

For reporting speech as indirect, we shift tenses, it's called backshifting, even though there is no time shift, hence no tense shift in the sense you are envisioning 'tense'. In this case the tenses aren't being matched in your sense, we make the shift back to signal that it's indirect speech. Let's look at an example.

A: I'm going to New York on the weekend.

B: [to C] What did A say, C?

C: She said she is going to New York this weekend.

Does is match said, Debra? No, it doesn't. Could we have "tenses" that match, yes, but only in form.

C: She said she was going to New York this weekend.

Here the match isn't the past tense, in the sense,

I was in the gym.

where 'was' denotes a finished state of 'thereness'. The 'was' of 'was going' is only a past tense FORM, which we use as a signal to let others know we are not directly quoting another speaker/writer.

Of course you're right that many times "tenses" do match but that is for semantic reasons, not syntactic ones. The reason there is no Concord of Tenses/Sequence of Tenses in English, despite what prescriptivists have long said, is that language has to be able to describe all potential situations and that wouldn't be possible if we had to follow these artificial strictures.

[Ebrown, take note of yet another artificial rule as opposed to a natural one.]

1. If she had taken that poison she would be dead now.

In 1. do the tenses have to match, Debra?

1a. ?? If she had taken that poison she would have been dead now. ??

You too, Debra, are much too intelligent to be repeating this type of nonsense. This has been the mantra of prescriptivists for centuries, but there is no factual basis for it whatsoever.

Do take a look at those books I suggested in my last post. You'll be amazed at what language really is, an exceedingly complex thing of beauty and you'll know that you were badly cheated in the grammar that was offered to you over your school years.

Why didn't anyone ever ask their teachers how something as complicated as language could have been described by such a rail thin pamphlet like Strunk & White? Maybe some did. It would have been interesting to hear the replies.

I tend to like what Debra writes, I find her stuff most congenial. And correct too, of course.

Hello McTag.

I don't tend to, I do like what Debra writes and even when she's not congenial, though that's certainly not the case in this thread, I agree, she writes well.