BRIDGE

South dealer. North-South vulnerable.

The real test of a partnership lies in its slam bidding. Most slams require an extensive series of bids, and it is vital for both players to make as descriptive a bid as possible at each turn.

Examine this sequence that enabled the worldfamous Sharples twins of England, Robert and James, to reach an excellent grand slam. Their bidding was natural throughout. They used no artificial bids, except to show first or second round controls when deemed necessary.

The one-club bid was normal, and so was the two-spade response, which indicated 17 or more points and interest in a slam. At this very early stage, South could already assume a small slam, since he had 17 points opposite the jumpshift.

However, South did not know where the slam would play best or whether a grand slam might be possible.

He therefore bid three diamonds, showing his second suit while at the same time identifying clubs as his longer suit, since he had bid them first.

North then showed club support by bidding four clubs, which established clubs as trump.

From this point on, firstand second-round controls were shown. South's fourheart bid indicated the ace of hearts, and North's five diamonds showed the king in the suit his partner had bid earlier.

South replied in kind with five spades, identifying possession of the king, and North, delighted as the last piece fell into place, jumped to seven clubs, which was easily made.

It is interesting to note that neither player resorted to Blackwood at any stage. The four aces were located by inference, and the absence of one king -- an unimportant one -- did not stop the Sharples from reaching the grand slam with only 33 high-card points.