1N-2D opener generally bids 2H.  The only way to super accept H is to bid 2S.

 

1N       2D       2H       2S=relay forces 2N then:         

3C=4441 or 4450 force. 

3D=4414 or 4405 force.

3H=5/5/majors invitational.

3S=5/5 majors force.

3NT=5/5 majors but also minor suit stoppers

4C or 4D = fragment (and void in 4th suit)

1N       2D       2H       2N=natural, opener can bid 3C, 3D to further game try.           

1N       2D       2H       3C,3D=natural force does not promise slamish values.  

1N       2D       2H       3H=natural invitation    

1N       2D       2H       3S=long H forcing. 3N asks singleton responder then shows singletons at 4 level (no void step available)

1N       2D       2H       3N=natural      

1N       2D       2H       4C=slam try no shortness, opener bids 4♦ last train

1N       2D       2H       4D=    

1N       2D       2H       4H=slam try weaker trump no shortness           

1N       2D       2H       4N=quantitative

1N       2D       2S        Only heart super accept.  Responder bids 2N with heart length.  All   other responder bids shown hand types of relay above.