1. Middle school is the same.

2. Elementary school is the same.
3. Middle school is not the same as elementary school.
4. Middle school is different from elementary school.
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In each sentence, Is 'same' an adjective or a pronoun?

#3 is the same as #4 in meaning.
If 'same' is the opposite of 'different,' is 'same' an adjective? Or is 'same' a pronoun? • English - Reed, Friday, March 11, 2016 at 11:10pm
It's an appositive. "She is my teacher." "She is not my teacher." 'teacher" is the appositive, in this case a noun. "same" is an adjective in these sentences. "...is the same...", used as an appositive, as in "The tree was tall."

• ZPPSS English - MAHESH, Sunday, March 13, 2016 at 5:43am
PAPER
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1. Middle school is the same.
2. Elementary school is the same.
3. Middle school is not the same as elementary school.
4. Middle school is not the same as elementary school (is the same).
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Q1: In each sentence, is 'same' an adjective or a pronoun?

Q2: Does #3 mean #4?
Q3: What is the part of speech of 'as' in #3?

The word "same" can be an adjective, adverb, or noun, depending on how it's used.

In all these sentences, "same" seems to be used as a noun since the word "the" is in front of it. In those sentences, "same" (as a noun) is used as a predicate nominative (or predicate noun).

In 3 and 4, "as" seems to be used as an adverb.
http://www.macmillandictionary.com/dictionary/british/as

Q1: In each sentence, 'same' is used as an adjective. It describes the noun it is modifying.

Q2: No, sentence #3 does not mean sentence #4. In sentence #3, it is stating that middle school and elementary school are not identical or equivalent. In sentence #4, it is further emphasizing the difference between middle school and elementary school by stating that they are not the same.

Q3: In sentence #3, the word 'as' is a conjunction. It is used to compare middle school and elementary school and show that they are not the same.