After partner opens a weak 2, it has become fairly standard for a 2NT response to be an artificial enquiry.
Why?
Since we already know quite a lot about partner's hand, we ask for a little bit more information to give us the full picture - which will put us in a good position to decide the way forward.
So, I am talking about this situation
*2NT is artificial, asking about the hand - often referred to as Ogust.
Partner has asked us about our hand, what are we now able to say?
Option 1: Easy, simple and effective responses.
My recommended responses, which happen to be the simplest
| 3 of any other suit | shortage, and at least a decent hand, not a minimum |
| 3NT | good hand but no shortage |
| repeating 3 of your suit | bad hand / minimum |
So in this example, we would have the straightforward bid of 3♥, showing heart shortage.
*2NT is artificial, asking about the hand - often referred to as Ogust.
I like this structure because showing shortage always puts partner in a good position to gauge whether our hands complement each other, whether 3NT is appropriate, whether slam is in the picture, etc.
Related: Points opposite Shortage: Part 1 - Fundamentals
Option 2: Good or bad hand, good or bad suit
Some players like these responses
| 3♣ | Minimum hand, and bad suit |
| 3♦ | Minimum hand, but good suit |
| 3♥ | Maximum hand, bad suit |
| 3♠ | Maximum hand, and good suit! |
The advantage of this approach is you might stay out of for example 4♠ if you know partner has a bad spade suit, you might favour 3NT instead on some occasions, or you may just stay in a partscore.
It is also useful sometimes to know whether partner is a maximum or minimum hand.
Contrast with the two approaches
Option 2 gives you more info about the suit quality. Option 1 focuses on showing shortage, as a useful way to evaluate the partnership fit. Both are completely playable and fine, its mostly a matter of style and preference.
As mentioned I prefer option 1.
I've written a more thorough article on weak 2's - check here: Weak Two Bids in Bridge: Opening and Responses
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