Question

a statement about what will happen in the future

(What is the part of speech of 'what'? Is 'what' an interrogative pronoun or a relative pronoun?)

Answer 1

In this (not a complete sentence yet!), "what" is an interrogative pronoun. It's introducing an indirect question.

Answer 2

Thank you.

1. a statement about what will happen in the future

2. a statement about the things which will happen in the future

(What about this one? Is #1 the same as #2?)

Answer 3

Both mean the same thing, except that 1 has that<b> indirect question</b> in it introduced by "what," while 2 has a <b>relative clause</b> introduced by "which."

http://speakspeak.com/resources/english-grammar-rules/questions/structures-of-indirect-questions

http://www.chompchomp.com/terms/relativeclause.htm