This is modified because again the small range of opening a major
In all cases it promises at least 4 card support
3♣ is 8-10 points and opener can bid up the line if distribution points can get them to game
3♦ ask partner to bid game with top of the range probably need exactly 10 points to bid game
3♦ is 12-13 HCP
3M is weak < 8 HCP
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