Annotated chess game

After working so hard to create the right circumstances for the capture, now was the time. 41. Qxd6+ would have won two pawns straight away.

Michael is right. But, it's even more then what we posted. As in the aftermath of winning those pawn, he'd win up with two isolated pawn which would be overwhelming for black. In other words, it would be more then black, "could chew off".

Beware of repetitions!

Exactly, and by that, 3 fold, as noted earlier. Don't forget that earlier, if black repeated the same King move, he would've been able to declare a draw since the same position repeated twice there.

Find the best move for white.

Like before, it was 43.Qxd6+, winning two pawns and isolating his pawns, as 44.Qxc5 would be to follow later.

Once again, be weary of the position repeating.

This time, you found the best move.  

What should white do now?

Correct was 46.Qxc5 On top of what I mentioned, including his isolated pawns, you'd have an unstoppable, passed pawn. And, it would just about time for black to resign.

I would have played 46. Rg6 and I think black will have to trade queen for rook to avoid being checkmated.

This will also do. However, be weary of his Queen, with that pawn.

What should white do now?

Best was 48.Qd6+ and this would've won another pawn. As then, the follow up would be Qxe5, pinning his Nf6.

He had to play 48....Ne8, though after 49.Qcc5ch or 49.Rg6, Black could hardly hope to survive long.

?? He's now out of good moves since you're about to capture his Queen which is even worse.

White threatens mate next move. A bit of a see-saw game, this. Black set up a great chance in the middle game, but failed to realise the opportunity that presented itself. Gradually Black slid into a losing game from which he never recovered.

Yes, ION explained it better then I could. But, also, be weary of repeating checks, Erika. As after you had the winning game, if black repeated the same move to get out of check, he would've been able to declare a draw by repetition. That's something that you've got to pay attention to, as the last thing you want to do is draw a won game.