Replace the underlined part of the sentence with one word from the options given below:
 John is a person who collects stamps.

Which one of the following is the correct meaning of -
 The study of human behaviour and societies:

Which one of the following is the correct meaning of -
 Killing of self -

Which one of the following is the correct meaning of -
 That which cannot be heard.

_______ teachers prefer a class that is fairly consistent in having pupils of the same level. 

We could barely get any information at the airport _____ people seemed to have _____ idea about the flights.

Choose the appropriate article given in the options:
 Copper is _______ useful metal.

Choose the correct option from Assertive to Exclamatory transformation for the sentence given:
 I wish I had wings of a dove.