Game Try bids, Cue bids, Opposition suit bids.

1) What is a game try bid?

You   Opposition   Partner   Opposition  
You open 1 of a suit   Pass   2 of that suit   Pass  
A new suit is a request to Partner!              
               
i.e.              
1♠
3♣		   Pass   2♠   Pass

This 3♣ bid asks Partner what his holding in the club suit is, and is called
a trial bid (a Game Try). It will always have 3+ clubs.
It will be made on a hand such as:
♠ A Q 7 4 2    ♥ A 10    ♦ A J 10    ♣ 7 4 2   

Partner will help the conversation by bidding as follows:
1♠
3♣		       2♠
3♠ (sign off) 		    Hand 1: ♠ K 7 2    ♥ 7 5 4    ♦ K 6 4 2    ♣ 8 6 5
minimum, only 3 card spade support, 3 losing clubs. You do not want to be in game
1♠
3♣		       2♠
**3♥		     **Hand 2: ♠ K 9 8 4    ♥ 6    ♦ K 8 7    ♣ 10 9 8 5 3
8 losers; you should have bid 3S over 1S. So now, bid 3♥ – a feature – probably a singleton, showing a suitable hand, and telling partner that you want to be in game.
1♠
3♣		       2♠
3♠ (sign off)		    

Hand 3: ♠ 10 9 8 3    ♥ K Q 4    ♦ 5    ♣ 8 6 5 3
Again, a minimum, but with 8 losers. However, this time, they are the wrong 8 losers. If partner had bid 3♦ (seeking help in the diamond suit), you would have bid 4S direct.

1♠
3♣		       2♠
4♠ (bid game) 		    Hand 4: ♠ J 10 9 8 5    ♥ K 10 8    ♦ 8 7 6 4    ♣ 6
The singleton club is sufficient to jump to 4S. Although you have got 9 losers, you have a decent 5 Card trump suit. When Partner makes a game try/trial bid, your best possible holding is a singleton,
In the suit of the trial bid.
1♠
3♣		       2♠
****4♠		     Hand 5 : ♠ J 10 9 8 5    ♥ 6    ♦ 8 7 6 4 2    ♣ A K
**** With only 7 losers, you should NOT have only bid 2S on this hand. You should have bid 4♠ directly. So, obviously, you would bid 4♠ now.
1♠
3♣		       2♠
4♠
(On general values)		     Hand 6 : ♠ K J 10 6    ♥ 8 7 6 3    ♦ K Q 7    ♣ 5 2
This was a very good 8 loser hand, with all the points working – K J of trumps excellent, the King and Queen are in the same suit, also a strong holding. You can see 10 tricks – 5 trumps, a ♥, 3♦s
and a ♣ ruff in dummy.
               
Also.
             
1♠
3♣		   2♣   2♠   Pass Equally, this bid of the enemy suit is also a game try, again it should be made on a similar hand to the one above.
(♠ A Q 7 4 2    ♥ A 10    ♦ A J 10    ♣ 7 4 2)