its mate in 2 and not 3 isnt it?

"If Rook at E8 comes down to E1, Queen takes Rook; not checkmate.  Mate in 2 only occurs if black does not block the offense."

i can not understand this one! XT7

"right, look at the board its white move, and white queen goes to d2-h6, 

there is no check for king, 

if black rook at e8 comes to e1 its check mate for white,. 

there is no way to get that rook!!!!!"

Rajezkumar, I will presume you've seen the "solution" already.  Mate in 2 would be queen D2 to C3 where she still defends E1, then provided black foolishly slips on defense, she goes for the king at G7.  Black pawn G7 to G6 would make this impossible.