In a laboratory experiment, certain painful stimuli, such as needle

'Produced' and 'did' are action verbs. 'Have' or 'had' by itself can be a linking verb (extant verb or status verb) or a helping verb along with a part participle or with progressive tense. The point is that we cannot replace an action verb with a linking verb or a helping verb.
Example.
A year before last I trekked 3000 feet on the Himalayas. Last year I had only 2000 feet due to poor weather.
Here 'trekked,' an action verb, is being replaced by 'had,' which is a linking verb. In the context, 'had' means possessed.
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Correct Answer must be (D) for the highlighted errors in other options.
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The word "many" is used to modify something that can be counted
The word "much" is used when you're modifying something that can't be counted.

In this sentence we are referring to "the word --thrusts-- which is indefinite in number /not specified.
Going by the the rules for many and much- Should'nt the answer be -- twice as much instead of --twice as many??

Answer (A)?

your Understanding of the concept is correct here. but the issue is with its application.

"many" here is not used to refer to "thrusts". it is used for "painful sensations", which is something you can count.

Hope it answers your question.

egmat daagh

Why did is correct over had?

This is a question testing us on the distinction between countable and uncountable nouns and comparisons. Firstly, "stimuli" is a countable noun, as we can count how many stimuli there are - for example, 1 stimulus, 2 stimuli, 3 stimuli, etc. This eliminates A and C - "much" and "amount" is used for uncountable nouns. Secondly, for a comparison, we need an "as +....+ as" structure to come in a pair. This eliminates B and D. Hence the correct answer is C for the correct usage of "many" for countable nouns and "as +...+ as" structure for comparisons.

Official Explanation:

A. No. Quantity word. "Sensations" are countable (you have many, not much, sensations).

B. No. Tense. Don't switch tenses (from the simple past——"produced"——to the past perfect——"had").

C. No. Quantity word. "Sensations" are countable (you have many, not much, sensations) so don't use "amount". Also, don't switch tenses (from the simple past———"produced"———to the past perfect———"had").

D. Yes. Quantity word. "Sensations" are countable (you have many, not much, sensations).

E. No. Tense. Don't switch tenses (from the simple past———"produced——"—to the past perfect———"had").

Probably one of the stupidest question, people without medical background would just assume sensations are uncountable.

Even by knowing "many" is for countable items; "much" is for uncountable items. People would still get it wrong.

Bad question, thumbs down

I have the same doubt and out of all the explainations, non looks satisfying enough.

Please help, egmat

Flozy2, I'm far from a medical background but I could tell that sessions are countable. Think of the following sentences that are pretty common in everyday life -

1. I'm getting a weird sensation.
2. I'm getting a puking sensation.

^These sentences may not be the best, but they definitely tell you that sensations are countable. Use of the word "a" tells you that they are countable. You would never use the word "a" with an uncountable noun such as love, music, etc. Hope this helps!

UdayPratapSingh99, sharing my 2 cents while you wait for an expert reply.

Couple of points here -
1. Firstly, we are referring to "sensations" and not thrusts. And sensations are indeed countable.
2. Even if we were referring to thrusts, we would still need to use many as thrusts are also countable. The use of many vs much, does not depend on whether a number has been specified in the question or not, but rather on if the noun is countable or not. Thrusts are 100% countable.

The best way to distinguish b/w a countable and uncountable noun is to try and count it. If counting (1 noun, 2 nouns, 3 nouns and so on) makes sense then it is a countable noun. If this does not make sense, then the noun is uncountable. "1 thrust, 2 thrusts, 3 thrusts" makes perfect sense. I learned this method from egmat and it works like a charm!

I still do not get how we are counting painful sensations for the answer to be many and not much

I understand your concern. The concept of countable and uncountable nouns can sometimes be difficult to grasp, especially in cases like this one, where it may not seem obvious that we can count "painful sensations."

In this context, we can think of "painful sensations" as individual instances or occurrences of pain that a subject experiences in response to various stimuli. Since we can quantify these instances or occurrences (e.g., a person may experience three painful sensations due to one stimulus and six painful sensations due to another), "painful sensations" can be considered countable.

Therefore, we use "many" instead of "much" because "many" is used with countable nouns, while "much" is used with uncountable nouns. The correct answer is (D) "twice as many painful sensations as did," which treats "painful sensations" as countable occurrences.