Verbal Reasoning - Mental Ability Questions

Letters in the word                          Letters in the alphabet

SEQ                                                      SRQ

QUEN                                                  QPON

SEQUEN                                               SRQPO

ENTIA                                                  EDCBA 

The words are BE and HIND 

"The words in each pair are antonyms of each other". Here "opposite Relationship" exists. The Word Indolence and the word work are opposite to each other. Similarly the opposite of the word Taciturn is speak.

Indolence - Meaning of this word is 'Laziness'

Taciturn - Meaning of this word is ' Saying very little' , not communicating a lot.

Letters at the odd places of the word are written first and these letters are followed by letters at even places.

nec po tam => boys are studying

me tam sam => grapes are sour

tam po me => boys are grapes 

It is clear that "sam" represents "sour" in that code language.

Each term in the series is obtained by subtracting from the preceding term the number formed by the first three digits of preceding term
So,missing term is 4983-498=4485

As from the given conditions;
Order is
N O P Q R S T
Here the student standing in the middle is 'Q'.

From the above arrangements, M is to the immediate right of D.