Responder needs more trumps to raise (four to raise 1♦; five to raise 1♣). Since four card majors should be bid up-the-line, a raise denies a four card major. Once a minor is raised, the bidding must end in that suit or NT. Raises are inverted so a raise to two is strong (limit raise or better) and a raise to 3 is weak (preemptive). When vulnerable, a jump raise should be sound (8-9 dummy points) but when non-vulnerable it is much more wide-ranging.
1♦
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2♦: limit raise or better (limit raise as passed hand)
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2♥, 2♠, 3♣: stopper
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2NT: balanced minimum, side suits stopped
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3♦: unbalanced minimum
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3♥, 3♠, 4♣: extras, splinter
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3NT: 18-19, side suits stopped
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4/5♦: to play
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3♦: preemptive