After 1♥,I am 4th seat,but very hard to show my 16-18hcp with balance hand.
1- bid 1nt :1nt shows 11-15hcp with balnced hand at the 4th seat.
2-double : after pd's 2♦,re-bid 2nt shows 19-21hcp.
Now I don't know how to show 16-18hcp with balance hand.