Figure 2.4.4.4[White to move]

Avoid doing anything without first examining any checks you can give and their consequences. Here White has Rxg6+, which goes nowhere; but then he also has Qd2+ (don’t overlook backward moves!). Black is forced to move his king onto the same rank as his queen. Rd7+ forks them, and a move later Black wins a queen for a rook. Notice that attacks by the rook against a queen, like similar attacks by a bishop, only work if the attacking piece has protection; here White’s queen still guards the eventual forking square (d7) when it delivers check from d2.

Or you might get there this way: White's rook can attack the Black queen (and can do it with protection) by moving to d7. That's easy, but boring; but it might make you wonder whether the Black king could be pushed onto that same rank with a check. You find Qd2+.