Which do you think is the most usefull piece and WHY ?????

Queenless games is like playing a game without it's superhero. You will need to think more and coordinate your pieces better with them off the board. Personally i love Queenless games

me too they are funny and very interesting

Personally i hate queenless games.

The pawn. Often overlooked, but he can turn into a 2nd (or 3rd) Queen and deal out some serious damage. 

you know i have played a game where i ha only my king and my opponent 4 queens and a rook 
game DRAWN by STALEMATE LOL thats why you have to be carefull when you have many queens

the king of course, it does not matter if you have 9 queens if you got checkmated

Well sure, but in your game you didn't lose, did you? 

Also quite valid. Without the king there is no game!

thats an opinion
but i think the king isnt usefull he is  just vital

no i didnt lose

I think all peices are important because without 1 peice also we will not be able to play chess!

ok thats good too
Did you  heard of that? the chess federation wants to put +2 lines  in the chess board for more interesting games it will bve funny

Depends on the position, but generally pawns because they're a beacon for planning, give the king a natural pawn shelter, and the threat of promotion is pretty big leverage if you have that endgame advantage.  Chess is all about piece activity, but pawn structure and where the pawns point dictate plans, such as where one should attack, where to pile pieces for an attack, principle of two weaknesses usually involves forcing the opponent to move pawns on the side he isn't currently weak, etc. 

Next would be bishops as they defend weak squares and bishops without counterparts make an attack stronger, and they point to the side of the board you should play.  Tarrasch once said the future belongs to he who has the bishops. 

The queen is obviously the strongest piece so it's important in the sense that you don't want to lose it without compensation (otherwise you should just resign)

the pawn, because:

1- It protects the other pieces, which would die instantly without it.

2-You can sacrifice a pawn for position, ,,sacrificing the queen is just not the same...

3-According to my thread ''which is the most beautiful piece and why'' pawn is the second most beautiful piece after the knight

4-It can take another pawn without occupying the taken pawn square !!!! (en passant). The power of the pawn is incalculable.

5-It is comfortable to move ,in real life games, and it's perfect design protects your fingers from injure (doesn't happen the same with bishops)

6-It can become a chain

7-In contrast to the queen or king, it is the lightest piece, you don't have to overwork while lifting it...

i agree with you fr te en passant it can be very usefull many times

i like the pawn promotion to a knight sometimes, it can be very useful in certain situations.

definitely a knight. unblockable checks force many moves.

I think the seventh is not really...a good response.

the knight

Hey! the knight can't even pass through this "barrier" or it will be captured if you try...So it's draw unless if you sacrified something...