challenging

Good.

great puzzle

Like other puzzles this week, the first move was difficult (for me) but the follow-ups were rather natural/obvious.  But I don't feel like I have "solved" anything until we analyse the continuations,.

not great!

difficult one

Simple, but knowing that a tactic was there made it easy. In an actual game, spotting this sucker seems quite difficult.

?????

i do not get it

The knight can be taken with rook because of the tactic that white can pull off:

Rd5 attacks the queen and rook, forcing black to make the queen run away. The black queen must stay connected with the a5 rook, otherwise white can simply capture with Rxa5. Next, white puts the king in check with the queen, aligning both queen and rook against black's lone rook. The king has to first move since he's in check. Finally, white wins the rook with the new Q+R battery.

I'm looking at prativa's puzzle that he posted on page 2.